Contribute
Register

A new iMac G4 Mod with up-to-date hardware and unchanged appearance including pro speakers

Status
Not open for further replies.
Main features of this Mod:
1. Built over industry standard platform(thin mini-itx), easy to upgrade with newest hardware
2. Original working IOs (Ethernet, 3*USB2.0, 2*USB3.0 via original 1394 port) over unchanged appearance
3. Native Pro Speakers support through original 2.5mm mini jack and class-d amplifier with no mod, plug and play
4. Original internal speaker supported
5. Jack detection enabled for original 3.5mm headphone jack and 2.5mm mini jack.
6. Original power indicator LED and Microphone inside LCD panel
7. Newest standard Wi-Fi and Bluetooth support with original antenna
To be done:
8. Digital audio interface by reusing original 4-pin telephone connector (+5V,digital out, digital in, GND)
9. Mini displayport output by reusing the mini VGA port
Hats off to you. This mod is excellent, and a great first post. Your use of the original original components is amazing. The heat-sink solution is most elegant, but would like to know what CPU you are cooling and what temperatures you get under load.

Also It would be good if you could post some more details about Item numbers 2 (usb 3 by firewire) and number 9. I am especially interested in how you have achieved this, as it is something I still have to tackle.

Also out of interest I am wondering if you could provide more details about the PSU pinouts, conversion, on off control, etc, for other who may want to follow.
 
This is just great. :thumbup:

It would be cool, if you could post some more details such as pinouts and detail photos.

I've reused the original speaker connector in my HemiMac mod but used a new AMP.

MacTester
 
I've seen a lot of great mods on these forums, but this ranks among the very best.

How in the world did you figure all that out, and make it fit in the dome????


Excellent, 10/10 for sure.


Cheers!

Hi ersterhernd, thank you for your high appraisal:). After a glance at this board, I found so many great iMac Mods here which are so helpful if I could found this earlier. e.g. yours and MacTester's.
 
Hats off to you. This mod is excellent, and a great first post. Your use of the original original components is amazing. The heat-sink solution is most elegant, but would like to know what CPU you are cooling and what temperatures you get under load.

The heat-sink solution is just copied from original design of iMac G4. The CPU is G1620 with 55W TDP, a lowend one just for experimental purpose. A rough test shows the cpu temperature rises 20 centi degree at idle, while rises 45 centi degree at 100% load of both CPU and GPU.

IMG_1395_1.jpg

I'm now purchased GA-H87TN for haswell platform, and the CPU selection would be i5 4570s or 4670s, with 65W TDP, we will see the heatsink performance then.

GA-H87TN.JPG



Also It would be good if you could post some more details about Item numbers 2 (usb 3 by firewire) and number 9. I am especially interested in how you have achieved this, as it is something I still have to tackle.

USB3.0 just added 5 pins (5~9) over USB2.0, so the solution is Pin1~4 go to original USB 2.0 port, Pin5~9 go to original 6-pin 1394 port. These 9 pins will be merged outside to a usb 3.0 female connector.

USB3.0_Pinouts.PNG

Regarding the displayport extention, my initial thought is reuse the min vge connector which have 15 pins. Though the displayport has 20 pins, some are just gnds for signal shield and some are just reserved. Later I found the female mini displayport connector can fit to the io cover very well by replacing the mini vga connector. This will offer higher signal quality.

dp_mindp.PNG



Also out of interest I am wondering if you could provide more details about the PSU pinouts, conversion, on off control, etc, for other who may want to follow.

I will try to add more details when implement the haswell upgradation.
Besides, Dremel's blog http://www.dremeljunkie.com/ is very place for the more details on PSU, LCD etc.
 
This is just great. :thumbup:

It would be cool, if you could post some more details such as pinouts and detail photos.

I've reused the original speaker connector in my HemiMac mod but used a new AMP.

MacTester

MacTester, I just read through your post on HemiMac, it's so great work and amazing we share some ideas similarly. At end of this mod, it failed to squeeze more space for full size DVD drive as I mentioned, I also considered to switch to intel NUC, which can be just put into HDD place. But I'm not sure if NUC provide good interface for extension, For example the jack detection for headphone?

To not affect the appearance, I also have planned to use touch sence and MCU for dimming, display on/off, fan speed control etc., but I never thought to drill on the dome. Since the capacitive sense structure is quite simple, it's possible to implement on a soft pcb which can be squeeze between the dome and the plastic housing. Besides just press, more actions like slide, wheel can also be possible.

capacitive_sense.png

A question in my mod, it's using +5V of HDMI to determine the backlight. But when the display goes to sleep, the +5V is still present, thus backlight is not turned off. What's your solution? I'm now trying to seek some IC can detect the TMDS signal, but if there's a simple way?
 
love this mod most of all as it seems to be the least difficult , ssd?do you have more pics ?
 
MacTester, I just read through your post on HemiMac, it's so great work and amazing we share some ideas similarly.

...

A question in my mod, it's using +5V of HDMI to determine the backlight. But when the display goes to sleep, the +5V is still present, thus backlight is not turned off. What's your solution? I'm now trying to seek some IC can detect the TMDS signal, but if there's a simple way?
Have a close loo at Post 87 of MacTester's build. The solution is the front panel power indicator (LED), that comes from a header on the motherboard. Intel motherboards (assume others as well) allow you to display sleep mode in a different LED state e.g blinking. On the NUC you can set this a dual colour mode which reversers the polarity of the signal for dual colour LED's, this can easily be detected and used to drive micro controller or other inverter cutout circuit.

Kiwi
 
Wow, simply amazing mod!

:thumbup: Bravo! :clap:
 
Status
Not open for further replies.
Back
Top