iMac G4 20" All-In-One ECX Mod - Completed



Left Side with computer on



There are still some small tweaks I may make, but for all intensive purposes this mod is now complete.  I completed the ports with one exception, I still haven't figured out how to handle the apple cinema display's power cable.  As it plugs directly into its power supply, there is no "female version" of this plug.  I think I'm going to experiment with different connectors, but for now the middle section with the power cables is unfinished.  I am also likely going to add an HDMI extender for "HDMI" out capabilities.  The onboard intel graphics are 1080p capable and I have included a bluray player, thus this computer may make a reasonable HTPC.

 

 

The power cables come out the back.There are 4 USB cables to the left.  The firewire ports are empty (may put HDMI out here).  To the right is an ethernet and Power LED, HDD LED.  The original power button is also operational.



The computer currently boots to windows.  As I explained in a previous post, the onboard graphics work, but with limitations on hackintoshes.  To get snow leopard on here, I would have to purchase a 1.8" SSD (it will not reognize the compact flash) - which I would be fine with as long as it was fully functional.  This appears to be a problem that many people in the hackintosh community are working on, so if a solution presents itself, its certainly first on my list to add.  As I am showing this right now to demonstrate a hardware hack, I again respectfully askto refrain from comments about how sacreligious it is to see windows on an iMac etc.

The drive is a "killer" in this mod.  Any slim or non-powered drive tray is not able to push open the door.  The drive probably occupies 60% of the "usable volume" of the entire dome and it has been the first thing to go in most iMac G4 mods.  Because of the ECX board I was able to spare the drive and use a bluray to boot.  Although optical media is getting somewhat useless, its still one of the signiture features of this computer.  And if I do go the HTPC route it will be a valuable addition.

I also need a proprietary adapter for onboard audio.  If I use HDMI out for an HTPC I won't need onboard audio and I have a griffin audio adapter which allows me to use the native speakers, so its not a necessity.

As you can see this is certainly NOT a hard core gaming computer.  But it is a good machine on par with the current generation of mac minis.  It is noticably faster than the (2 generations ago) mac mini that I currently have hooked up to my touchscreen mod.

I highly recomend this mod.  Even if you could get the native inverter working with an external power source you would still need to manage a 24V, 12V 5V, and 3.3V lines.  The LCD controller for the apple cinema display does it for you.  Except for that this is really no different than the DVI hacks for the 15 and 17".  This is much easier than the previous mod as you do not have to do any cutting or modifying of the case itself.

The 3 things that do concern me about this mod are

1) Not a touch screen - to keep the weight neutral and the mod as close to original as possible I did not go the touchscreen route.  I am currently experimenting with optical sensors.  If I could incorporate these into the bezel it would be essentially weightless and would save me from having to put a poor resolution piece of plastic in front of the monitor display.

2) No Snow Leopard - I didn't want to put a troublesome video work around on just to say its Mac OS X.  I'm going to keep my eyes open and maybe Lion will be different or maybe the next generation of ECX board will have a different graphics option.  And that brings me to #3...

3) The future of ECX boards.  I love this form factor.  Its not only perfect for this mod but I could see doing a lot with it.  The board was developed with the intention of having the power of a mini itx board in a smaller form factor.  But, this is the only small form factor board that I've found that uses something superior to an Atom processor.  As these boards are not mainstream, there is no guarantee that they will be upgraded to anything like sandy bridge architecture.  While I was hoping to see the next generation mini become "smaller", for my purposes they actually became "bigger".  Yes they are thinner, but they are now actually harder to fit within the iMac G4 shell.  But, for now I'm going to enjoy this mod.

I hope people find this helpful and I would love to see people replicate or improve upon this mod.  Starting out I did not think a core 2 duo all in one was possible with the native iMac shell - especially not the 20", but here it is.  As always, I welcome all questions and comments.

Thanks for reading.

Finishing Touches and Ports

Although, I was disappointed by the limitation in operating system - I'm still excited that this is a true 20" all-in-one complete with blu-ray drive.  So, I want to make it as professional as possible.  I took the base apart to better secure everything.  Here you can see the ECX board elevated and secured to the Blu-ray drive.  I am using the native drive caddy - but did have to dremel off the top part of it to make room for the board.

As the CPU fan fits right under the dome I elected not to add an additional case fan.  There is no hard drive or power source and this is a low power consumption board, but I may revisit this depending on my cpu temps.  I had also initially placed a wifi card at the top of the dome, but the reception was too poor, so I have removed this and will use an external usb card.

For ports, I have chosen to use mostly extenders.  I find wires easier to deal with than circuits.

To cement things into place modeling clay/epoxy works well.  There are multiple kinds, but the basic idea is to mix equal parts to two compounds which begin to harden when combined.

The first thing I secured was the power button, placing a small momentary switch right behind the native iMac G4's power button.

The Right sided ports were where the ethernet, modem, and audio jacks were for the native iMac G4.  I have replaced these with a ethernet splitter and the power led, hdd led.  In the picture below you do see an audio header, which I was originally going to use, however, the ECX board uses a pin layout that I was unfamiliar with.   So I held off audio out for now and incorporated the two led lights.

The left sided ports consisted of 2 fire wires, 3 USB and a display out.  I opened up the display port somewhat to allow another USB port.  Because I am worried about power constraints (I'm using a 60 watt power supply).  I wanted to make sure I used some powered USB slots.  Fortunately I have another power supply coming into the base in the form of the Apple Cinema Display.  The controller gives 2 USB outs.  So two from the mobo and 2 from the cinema display = 4 total.  The firewire ports i am leaving empty for now.  The cinema display does allow for 2 firewire connections and I could add a firewire PCI express at some point.  I was also thinking about cutting a hope between these and putting an HDMI extender for use as a second monitor when needed.

Now that I have the basic layout I apply the molding.  It usually takes a good 24 hourse to harden.  I will use the center for the two power supplies.  The DC for the motherboard will be a simple plug, but unfortunately because there is no female version of the cinema display power, I am likely going to have to simply "run the cable out the back".

 So I place the drive caddy with bluray and ECX and secure it as it was designed to be.  After the ports dry I will secure them to the bottom of the dome, secure the Apple cinema display's LCD controller to the bottom and close the base.

As always, questions and comments are welcomed.  But, this should be complete within the next few days.

Advice to Modders

I hope this doesn't come across as preachy, but I just want to give some advice to those of you new to modding the iMac G4.  I have disassembled and reassembled this computer so many times I could probably do it blindfolded.  There are a few aspects of modding this computer that have led to a lot of frustration for me, a few pointers, hopefully, will help some of you.

iMac G4 Neck with Cinema Display Wires

1) Do not be scared to open the neck.  Its not hard, does not require special tools, and is not really dangerous.  I have written on this blog about the exploding neck because I had read about it myself.  I have knocked the spring off its moorings numerous times and that just means a lot of work to pry it back up into position.  I've had an open neck fall off the table, I've left necks open for weeks at a time, and have never had the spiring fly off.  I wouldn't throw an open neck as hard of you can against the wall, but you also do not have to handle it like its plutonium.

2) Do not put more/thicker wires into the neck than it can hold.  Just because you can get it through the holes does not make it a good idea.  When you overcrowd the neck, you'll start to hear grinding and some wires will wear down as they are pushed into the hinges of the neck.  The iMac G4 has 4 wires that go through the native neck.  When you replace wires, take out what you're not using and aim to have about the same "volume of wires" as the native neck comes with.  To get wires through the neck all you have to do is push a wire that is already through backwards and  tape about 1/2 an inch of the wire you want to get through to that wire and pull it through.

3) When you can't get a signal replace the black wire.  I have heard from many people who can not get the 17" DVI hack to work.  I know what the problem is - its the black wire.  If one wire isn't touching then there is no signal.  Too much solder on these wires causes problems.  Even if you get a strong signal on the mutimeter, crosstalk can result in color changes, flickering image, etc.  The wires are simply too small to reliably work with.  Give it a shot and try to spare the pins that are attached.  But, if you need to - replace them.  Replace them with what you may ask.  I used an apple cinema display's wiring here, but these are no different than any TMDS cables and the easiest place to get TMDS cables - take a DVI cable and strip it.  You will find 4 wires that have three wires bundled within them, these are the same as the 4 wires within the iMac's black wire.  Solder the pins to the top and you're set.  Even though it will be four wires to one, they are thinner and if you need remove the led/microphone wire go ahead and do it.  For my current mod, I have repaired problems with the black cable numerous times, I finally decided to replace it, with the apple cinema display's wires and haven't had a problem since.

4) Get rid of the Torx-6 screws.  These are the most troublesome screws I have ever worked with.  On the bottom of the 17" and 20" iMac G4's monitor housing you will find 3 screws that require a Torx-6  screwdriver to open.  These are the screws that keep the monitor housing closed.  I have never seen screws that strip easier despite using the appropriate tool.  6 points on a tiny screw is very close to a circle and once you start stripping it - its already too late.  Chances are good that you may have to open up the monitor housing again at some point for upgrades, repairs etc.  Act preemptively and replace these with small phillips screws - it will save problems later.

5) Want an All-In-One? Consider an 3.5" ECX or other small form factor board.  Although mini-itx or a mac mini motherboard are the most popular choices neither of these is ideal from a size/heat perspective.  ECX's can fit at the top of the dome in place of the native HDD where heat won't be as big a problem as it would with a mini itx at the bottom of the dome.  They don't require an atx power supply and come with a variety of additional options including PCI-E mini or x4, Compact Flash etc.  Processors range from Atom to ULV Celeron to Sandy Bridge Core i processors.  This allows you to keep the full drive if you want and allows room at the bottom of the dome for ports at the back.  Although not nearly as expandable as a mini-itx mobo, with such limited space in the dome, this isn't likely to matter.

6) Do not sacrifice stability for power.  The mods I post don't include many mods which failed.  Most of these initially worked but failed because I tried to force things.  If you have to use all your strength to push your mod closed to screw it in, it will not last.  If you cram things in between the motherboard and the air holes, your board will overheat.  One mod I did post that was going to fail was the 20" TMDS to LVDS Conversion.  Keep expectations in check.  If you have a 17" monitor running at 1440x900 you don't need SLI or Crossfire.  Having it turn on and having a critical problem like this is worse than it not working at all.  If it doesn't work you can at least start troubleshooting what went wrong, these problems like the 20" TMDS to LVDS usually mean complete redesign and many of the parts have to be repurposed or replaced altogether.

Hope this helps.

Hackintosh Blues

Now that the large hardware assembly was completed I was able to move onto the small hardware components and software.  As I have said before I myself don't love hackintoshes, but I did want to give it a shot with this computer to make it as close to the original as possible.

Courtesy of Logic Supply

I was worried about using a compact flash as my primary hdd and  it turned out to be justified as no matter what bootloader I used or how I formated the partition, I could not get the snow leopard DVD to recognize the drive.  The KEEX motherboard does have 2 sata ports, but only one sata power connector which is an a single connector tied to the first sata port.  However, with a SSD power use would be minimal so splitting the sata power should not be a problem.  Although it is a tight fit in the dome, I am able to fit probably a 2.5" ssd, but to play it safe I was looking into 1.8" drives.  However, before I payed for the drive I wanted to make sure there would  not be any problems with the hackintosh build but very quickly I learned that the onboard graphics is likely to be a major problem.

As you can see the board uses GMA 4500MHD graphics (Intel GM45 chipset).  I believe this is intels equivalent to the ion 2 platform.  Now with significant hacks it appears people have been able to force resolution in snow leopard to get above the default resolution, but there are still major problems and to my knowledge no one has been able to enable Quartz Extreme/Core Image with this chipset.  So, I could either 1) Buy the SSD  and install snow leopard the best that I can.  2) Use the PCI-express x 4 with an ion graphics card (this will likely requiring removing the hard drive as it is unlikely to fit as is.  3) Hold off for now - formally install windows or linux and wait to see if a solution presents itself.  As I've already spent FAR too much money on this mod, I've decided to hold off and work with Windows or Linux for now.

But, please if anyone has any knowledge about either the issue of booting snow leopard from a compact flash drive or the Intel GMA4500HD graphics problem help would be appreciated.  Thanks.

20" All-In-One Mod - IT WORKS!!

This mod is far from finished but in this test above it is completely sealed up and working beautifully.  This uses the unaltered iMac G4 exterior (base and monitor) and incorporates a Core 2 Duo Penryn Processor ECX motherboard.  What's more is that I was able to spare the disk drive and used a blu-ray drive.

Now its late and I'll have more specifics as I put the finishing touches onto this mod, but to start I'll tell you that the top half of this mod is the native iMac G4 - I used the native lcd glass and inverter.  From the cinema display I used the wiring and the lcd controller board.

As you can see in the picture above the only "flaw" with this design is that the power bricks (monitor and motherboard) are external.  This was done for both space and heat reasons.

The Notorious Black Wire

Apple cinema display cable

The major work for this mod (as is the case for most iMac G4 mods) involves the neck.  As I mentioned in a previous post, because the LCD controller for the Apple cinema display sends out more wires than the iMac G4 motherboard did (27 vs 21), an extra wire is needed.  I used an extra grey wire from a different iMac neck to make up the difference and put in in place of the LED/Microphone wire.  However, partially due to my own mistake, I was having difficulty with the black wire of the iMac G4.  This wire handles the color channels.  It contains 4 wires which are in turn made up of 3 wires (a positive, negative, and ground).  These wires are impossible to deal with, they are frustratingly thin and fragile.  And numerous color distortions I made a decision I would highly recommend.  I replaced the black wire with the 4 individual channels from the apple cinema display.  As you can see, I removed the rest of the cable  leaving only the JAE adapter and the 4 channels with 3 wires each = 12 total.

I reopened the neck and in place of the black wire I put the 4 individual channels from the apple cinema display (they are the "gold" wrapped wires).  I was concerned that they may not be adequately shielded, but this has not seemed to be a problem.  So the neck to the right contains:

A) The native inverter cable from the iMac G4 - untouched
B) The native grey wire from the iMac G4
C) An additional Grey wire from a different iMac G4 neck - this is in place of the LED.microphone wire
D) 4 color channel wires from the apple cinema display - in place of the black wire

As the overall size of the wires is about the same - they fit without too much force needed.

The base I put together very quickly just to test it.  Putting the ECX on top of the drive and the lcd controller at the bottom.  I had previously wired the power button for a different mod, but to test it I just ran USB extenders out the back.  I did put bluetooth at the top of the dome which seems to work well, but the wifi signal at the top is terrible and this may have to be externalized.

Everything is quite loose right now so it will all have to be secured.  The I will wire up the ports in the back.  Likely 3 - 4 USBs, ethernet, and the power for the motherboard and monitor.  But these are relatively small things.

I am also hopeful that the board is hackintoshable, I am not sure about putting snow leopard on a compact flash drive and if anyone has any experience with this - I'd appreciate a few pointers.  When I complete these last few touches I will post a video of the mod.

What blows my mind with this mod is that the goal has been to update the G4 (preferably 20") to a modern intel processor.  I have to admit this one accomplishes that goal better than any mod of mine or that I have seen to date.  Yet, it may be the easiest one to do.  I'm not saying its simple, it does involve opening and rewiring the neck and soldering.  I realize the cost in obtaining the ECX board, the iMac and the apple cinema display components, but if you have the equipment, this can probably be done in a day or two.  I'll post a pinout in the next few days to show exactly how I wired it up, but in the meantime please feel free to ask any questions.  Thanks.

Update - The Native Inverter and LCD Glass

First let me start off by saying that I did something very stupid despite me writing not to do this time and time again.  I soldered the DVI connector on without putting it through the hole in the dome.  So I had to cut and resolder and for those of you that have never seen the components of the black wire of the imac neck, I can tell you it as an absolute nightmare.  They are composed of 4 wires in which are 3 wires; a red (+), a green (-), and a ground.  The red and green wires have a small plastic coat surrounding a single wire that is the size of a hair. When I set up this initially I had the bottom pins on and was able to use a tiny dab of solder, having to resolder these tiny wires, wire to wire has caused signal problems.  Keep in mind even one failed connection will give you no image whatsoever, so a multimeter is very helpful.  But poor connections or poorly shielded connections will result in color distortion.

That said there is some very GOOD news.  The native LCD for the Apple cinema display (LM201W03) needs to be modified to fit and although it fits, I decided to try the native iMac G4's (IDTech 20.1") lcd glass and it also appeared to work (though until I have a perfect image I can not confirm this 100%).  So it is possible that the only thing you may need is the LCD controller board from the apple cinema display and the cable to get this mod to work as the native G4 inverter has been confirmed to work and the native LCD glass appears to work.  This would be quite helpful as you can use a broken cinema display with a cracked screen.

 To the right you see the mod to date.  The top monitor housing closes as easily as the original as it uses the native inverter and the native glass.  Because I wanted this mod to be as close to the original as possible - I actually purchased a new monitor housing and base cover from ebay as most of the broken used iMacs I have acquired tend to be yellowed or scratched.

You can see the monitor from the front, side and back.  To the right of that is the lcd controller and ECX motherboard.  The ECX boots from a compact flash card located on the underside of the board.

The ECX board is the size of a 3.5" drive.  My plan is to mount the ECX board on top of a blu ray drive in the native drive caddy.  (essentially taking the place of the native hard drive).  As the CPU fan will be sitting at the top of the dome, I will not need a fan, so I should be able to fit Wifi and Bluetooth at the top of the dome with the vent holes.  As I will not be using the native power supply I should have room around the ECX board to fit connectors.  The lcd controller board will replace the native iMac G4's motherboard at the bottom of the dome below the drive.  As its smaller than the native motherboard I'm hoping to have room to wire up some rear I/O ports.  The only downside is that this leaves no room from the power supplies for both the monitor and ECX board.  They would fit in the drive caddy and using a splitter a simple AC plug could be placed in the back, but then obviously there would be no drive.  I have thought about using the native iMac's power supply, but I really need the room and in a similar experiment I fried a different ECX board in the past.

So, I'm going to keep them external.  For one the power supplies are small and this is a desktop computer, it won't be moved that much.  Plus, I have always loved the drive and by using blu-ray it can be useful.  Also, its gonna be tight in there and there is really no cooling system in place - so keeping hot power sources external is probably for the best.

I do think the system is likely to be hackintoshable - the chipset has been hackintoshed before (this is the Quanmax KEEX-4030 ECX board for those interested).  The thing that I have never heard about is booting snow leopard from a compact flash card - a 2.5" or even 1.8" SSD may have to be shoehorned in somewhere if hackintosh is your goal.

Here is the system booting (again notice the small resolution during the boot that I previously discussed).

This is where the frustration set in - with windows booting.  While I previously had a pristine image, after the resolder, the colors are unfortunately off.  A multimeter revealed all intact connections but I was getting some week noise at the wrong pins - so I suspect some interference or crosstalk.  I'm going to remove all the solder joints for the black wires and try redoing them with fresh connections and extra shielding.

To do this mod, I actually used cables from the necks of different iMacs.  There are the black and grey cables that carry the DVI signal, however the apple cinema display has "extra wires".  Some of these probably aren't necessary, but some of them are.  As a result, I had to add an extra grey wire from a different iMac.  I replaced the native LED/Microphone cable with this wire.  The wiring is somewhat difficult to explain.  If I continue to have difficulty with the black wire of the native iMac, I will likely change it to a different wire.  Likely either the equivalent wires from the apple cinema display or another grey wire.  Both of these choices would be MUCH easier to work with.  Either way when I do finalize how I wire the neck, I will post specific instructions.

While I am quite proud of some of the previous mods - this mod is actually much simpler and besides having to push some wires through the neck, a lot less labor intensive than previous mods.  In addition, if it does turn out, as it seems, that either LCD panel can be used, combinations of discarded iMac G4's and apple cinema displays can be used.  I would NEVER tear apart a working iMac G4 and couldn't bring myself to tear open my mac mini to try to fit it in the base.  I even hated even using a working apple cinema display in my previous mod.  Its always great to re-purpose otherwise useless parts.  But whats great about this mod is that there are so many different ways, but this one feels the closest to the native 20" iMac G4 that I've come so far.

Keep in mind that the KEEX-4030 uses the same Socket P Penryn Core 2 Duo chip thats in the previous and current generations of minis.  This ECX board is no slouch.  That said, if there was a problem with it, I think this is the mod that I would open up a mac mini for and try to put it in the base.

I'm hoping to figure out the wiring, clean up the image and start putting the base together this weekend.  But, as always all comments and suggestions are appreciated, but please no comments about seeing windows on the iMac G4 - Its the only operating system I currently have on a compact flash card.  Also feel free to ask any questions.

A Genuine iMac G4 All-In-One

Although I thought the previous 20" iMac G4 / Apple Cinema Display came out very well and it has become my most frequently used desktop, there were compromises that I had to make.  The two biggest ones were externalizing the computer (abandoning the all-in-one concept) and using the external housing of the apple cinema display.  While I think it looks good, it still is not the classic 20" iMac G4.  While working on a different mod, I realized there are two things I overlooked while designing and building the previous mod that would allow a genuine 20" iMac G4 all-in-one with an updated intel processor.

I was working on a project which involved using some of my spare components with a broken shell of an iMac G5.  These were mostly unused pieces from my iMac G4 mod.  This predominantly included a LG LM201W03 monitor from an apple cinema display (although the G5 I believe uses the same panel with some variations).   And the ECX board which uses a P8700 Penryn Core 2 Duo processor (the current mac mini uses the P8600).

Comparison of native iMacs DVD/HD to size of Bluray with ECX board

As it is the size of a 3.5" drive and it has its own  Compact Flash slot to use as a SSD, I had hoped to slot this into the G4 in place of the existing hard drive and create an all-in-one that even kept the DVD drive. However, when it booted it would not display at the required 1680x1050 resolution of the cinema display.

I had thought that the ECX board simply could not output at the requited resolution.  The ECX board has a PCI express x 4 slot, I attempted to add  a PCI express x1 Ion graphics card, while this fixed the resolution problem, the ECX ples the graphics card no longer easily fit into the iMac G4's chassis.

I was wrong.  The ECX board can support the resolution, it seems to have a quirk with the cinema displaythat it detects it as multiple monitors one of which is a lower resolution.  When I manually adjusted the resolution in windows and turned off the "phantom display", the display became full size.

Although I have not minded having the external mini, this board gives essentially the same power as the newest mac mini plus it has 4GB of ram and uses compact flash for a SSD, if its "hackintoshable" - I do not know yet.

I still did not want to alter my old mod in any way that may damage it, nor did I want repeat the same cinema display hack.  I wanted to use the existing iMac G4's monitor housing.  This brings me to the second thing I had overlooked.

I decided to use the Apple Cinema Display enclosure because the iMac G4's monitor enclosure fits the lcd panel and its specially made super thin inverter and NOTHING else.  And I was never able to figure out how to use the native G4 inverter without the G4 motherboard itself.   For the first time I decided to compare the apple cinema display's inverter to the iMac G4's to see if there was any way the cinema display's inverter could fit within the G4's monitor housing.  Thats when I noticed the 8pin connectors were almost identical.

The iMac G4 only uses 7 of the 8pins, however when the one was not connected, it would not turn off immediately when the computer slept, so I will have to make sure I have one extra wire going through the neck to use all 8 pins of the inverter.  To my surprise when all 8 pins were connected it worked perfectly.  If there was any difference I was unable to see it.

Being able to use the native inverter meant that I could use the native iMac G4's monitor housing with the Apple Cinema Diaplay if I could find a place for one more board - the LCD controller board.  The controller board is very flat but is not flat enough to fit withing the housing.

Comparison of iMac G4 bottom with native motherboard vs. ACD LCD controller

Unlike the inverter whose high voltage cables should not be extended through the neck, there is no reason why the lcd controller can't be placed in the base and its cables extended to both the inverter and LCD panel.

As it is just as plat as the native motherboard which I will not be using it can fit at the very bottom of the dome.

The only true nuisance with this is that although both panels use TMDS signaling, the neck needs to be modified.  The existing Inverter wires can stay, but by placing the controller in the base, there are a total of 27 wires that need to extend up to the neck.  The black and grey wires combined have 22 wires.  Plus I needed one extra wire for the 8th inverter wire, making a total of 28 wires.  To add additional wires, I did take apart the neck and change the microphone, lcd wire to an additional grey iMac TMDS cable that I had from a different neck.  Once I had all the connectors soldered on I was able to put the inverter and lcd on one side of the neck and the lcd controller and ecx board on the other.

Unfortunately it does not look like I'll have room for both a power source and a DVD/Bluray.  I will be able to fit one or the other.  Right now I'm leaning towards keeping the drive and having a power brick external.  I want this mod to look as genuine as possible, as such I'm forgoing anytouchscreen option.

Powering it on revealed a clear image:

Now to internalize it into an iMac G4 20" shell to see if it will fit.  This is the most hopeful I've been for a genuine iMac G4 20" all-in-one with modernized hardware.

As always, feel free to ask any questions.