MacTester57's HemiMac G4

[spence4]

Thanks, guys!

I know, that those goals are aggressive. After I've disassembled the base and did some measuring I have to say that it will be almost impossible to integrate a mini ITX board under the optical drive - it would fit, but there is only 15mm height available...

If I want USB 3.0 and an optical drive, I will have to wait for the Haswell NUC or will have to use the GIGABYTE BRIX GB-XM12-3227 (which only has 2 USB 3.0 ports)

MacTester

Hi MacTester,

Since you have your iMac in front of you and open, I was wondering if you might be able to answer a questions or two for me. If I didn't mind leaving the optical drive out, could a mini ITX board work? I would most likely use the Gigabyte H77N Wifi board that tony recommends with a low power IB, an i7-3770T most likely. I would plan on putting a 92 Noctua fan at the top of the dome and an SSD and 2.5 notebook HDD in one of those cases that is the size of one 3.5 HDD. Would most likely go with the Noctua NH-L9i cooler for the CPU. Would all that fit in there? It looks from the picture like an ITX board will fit, most concerned about the height of the CPU fan and the HDD and whether it will all fit. Any info you have would be much appreciated. Thanks.

Spence

 

[MacTester57]

Spence,

If there is no optical drive it should fit, but the room for HDMI and USB cables is very tight.

At the moment, I'm not able to measure.

MacTester

 

[spence4]

MacTester,

Thanks. I figured I would use a 90 degree DVI adapter in order to use the LCD. Do you think an HDMI --> DVI adapter --> would be a better solution? USB may be a bit trickier, but I just figured that for about 400 USD I can get the H77 and 3770T which is not that much more than the NUC. Gives me a lot more options as well. Thanks again for the feedback.

Spence

 

[ersterhernd]

Spence, I'd make a mock-up model of the mITX board and cooler first out of styrofoam or something, with correct heights, just to see if it'll all fit. I'd hate to see you spend all that money only to find out later that it won't work. I'm not saying it won't, but it'll be very tight at best. Just a thought.


Ersterhernd

 

[franchois]

Spence, I'd make a mock-up model of the mITX board and cooler first out of styrofoam or something, with correct heights, just to see if it'll all fit. I'd hate to see you spend all that money only to find out later that it won't work. I'm not saying it won't, but it'll be very tight at best. Just a thought.


Ersterhernd

i'd second that. I have an old mac mini (late 2009) and i'm able to fit the mac in the base, with some extension wires (3 USB, audio and mic.)

i can't put an ethernet extension and 2 mode USB cables.... and yet i didn"t put any PSU in it (i'll keep it outside)

Franchois.


edit: the mac mini without its cage and without superdrive (sorry for my english)

 

[rick26]

i'd second that. I have an old mac mini (late 2009) and i'm able to fit the mac in the base, with some extension wires (3 USB, audio and mic.)

i can't put an ethernet extension and 2 mode USB cables.... and yet i didn"t put any PSU in it (i'll keep it outside)

Franchois.


edit: the mac mini without its cage and without superdrive (sorry for my english)

Yeah but the mac mini 2009 is the older version and is smaller than a mini itx board so it wil be extremely tight.

Rick,

 

[MacTester57]

In the meantime, I've done some additional tests with my sleep LED controller. On the video, it's looking even better than the original Apple LED! In order to achieve the original brightness, a BC548 transistor at the PWM output was necessary.

See here:

A test for the LCD inverter brightness controller was also done. The PICAXE microcontroller even is able to act as a touch sensor controller!
Only a washer in a plastic bag is necessary! I intend to implement two touch sensors in the front of the base:

The PICAXE program for the touch sensor functionality:

See here:

MacTester

 

[ersterhernd]

Wow thats amazing stuff, MacTester! It'll be great to see it all put together. On a different note, any thoughts on your choice of processor? I think you're going with the NUC, but not sure. Waiting for Haswell to appear? Pls inform, as I'm at that point now too with my 2nd iMac. Just trying to decide with regard to a cost and performance balance.


Looks great so far...


Ersterhernd

 

[MacTester57]

Ersterhernd,

Thanks for the praise. I'm not yet sure, but I guess, that I will wait for the Haswell NUC, because I want USB 3.0...

At the moment, there is enough to do with the PICAXE microcontrollers. The next work will be the installation of both touch sensors in the base.

I'm not sure, but the video links in the last post seem to be corrupted. Here they are again:

Sleep LED comparison video

Touch sensor test

Working CCFL brightness control with touch sensors

As you can see, the CCFL inverter works flawless with a PWM modulated brightness signal (10 kHz) on the green neck wire.

MacTester

 

[ersterhernd]

That dimming touch function is nothing less than brilliant. Excellent!