Pixlas 4.1 Mac Pro mod

[XNorth]

Hi, just a question. theorically, the pixlas mod work with 1.1? (power mod for gpu)?

The question is the wiring ... is the wiring in the same order as the 5,1? Both PSU are 980W, so power shouldn't be a problem for the TDP of your GPU.

 

[lilins]

YES! I think i'll need to find out 🙂

 

[Surrat]

You would need to research the outputs on the 1,1 power supply and their wattage limits.
The wiring for the 1,1 power supply is different from the 4,1 and 5,1.

 

[lilins]

You would need to research the outputs on the 1,1 power supply and their wattage limits.
The wiring for the 1,1 power supply is different from the 4,1 and 5,1.

what i thought.

for me the simplest way would be to take the missing 150w from the 2 empty pcie slots, but i can’t find any kind of cable that would do this. 🙂

but a 1.1/2.1 pixlas mod would be muuuch cleaner

and with this: it’s not so hard

 

[lilins]

So, good news, the 1.1/2.1 pixlas mode is working. the r9 390x work. i have yet to do stress tests!

only issue for now. under el capitan, it is seen as radeon hd 8xxx 8gb and i have some display glitches in 2d (strangely in 3d all is good) anyone knows how i could set this up?

under windows it works as a charm.

 

[Macschrauber]

So, good news, the 1.1/2.1 pixlas mode is working. the r9 390x work. i have yet to do stress tests!
.

So what rails did you take ?
How did you rooted the cables thru ?

 

[lilins]

So what rails did you take ?
How did you rooted the cables thru ?

first i’ll stress test this, then i’ll make report with cable management and connexion.

here is quick picture:

 

[lilins]

first i’ll stress test this, then i’ll make report with cable management and connexion.

here is quick picture:

View attachment 764115

So, before benchmarks, here are the mod pictures:


The whole thing on the table:

PSU plugs: remove psu unplug the psu from case and remove it (undust it maybe)

The best tool for this (believe me, the chance your finger are thinner than mines is almost inexistant, and i had to use that to unlock the bottom lock of each plug

like i said it is useful, once you understood how it work you can remove them easily

They’re out and labelled on both plug and cables sticker

This is the easy connector i used. the ones from 4.1/5.1 pixlas mode are too big for this psu cable section. (standard easy connectore from car parts)

as you see the PCIe cable pass in the same location as all the other mlb / psu cable. easy with some tape to hold them together while passing them through the hole.

it’s easy

try to fix the easy connectors not too close so they won’t sit on each other and won’t block the optical cage.

here the PCIe cable pass under the Main Fan cage right under where mlb pcie connectors are located.

i have a few more pictures if you want but most of them are here!

at least the 375w r9 390x power up. i need to do stress test.

 

[lilins]

did a small furmark bench and stress, gpu load 100%

no issue

here are passmark scores:

Mac Pro 1.1(2.1) r9 390x 32gb sataII ssd dual x5365

https://www.passmark.com/baselines/V9/display.php?id=103253813321

Mac Pro 1.1(2.1) r9 380x 24gb sataII ssd dual x5365

https://www.passmark.com/baselines/V9/display.php?id=103093528573

Due to CPU bottleneck the 390x don’t give so much more power, but under windows i’ll try some trixx overclock

to give some point of view, this is my Mac Pro 5.1 vega64 64gb sataII ssd dual x5690 score

https://www.passmark.com/baselines/V9/display.php?id=103084755509

And i think i found the glitch issue under osx . i may need a DP cable, so i’ll try that!

 

[superparati]

Is there another website where we can find the PCI 8 pin end-open?
Moddiy doesn't take order right now.

Would it work if I take a classic cable and cut the end of one side?

Thanks

 

[h9826790]

Is there another website where we can find the PCI 8 pin end-open?
Moddiy doesn't take order right now.

Would it work if I take a classic cable and cut the end of one side?

Thanks

Yes, just cut the cable and remove the connector is fine. That’s just some super low tech stuff, nothing more than some metal wires with plastic cover. Doesn’t require any special tool.

I did evenrthing with my Swiss knife, just need a little patient to remove the plastic cover.

 

[superparati]

Yes, just cut the cable and remove the connector is fine. That’s just some super low tech stuff, nothing more than some metal wires with plastic cover. Doesn’t require any special tool.

I did evenrthing with my Swiss knife, just need a little patient to remove the plastic cover.

Thank you, I'll go for the classic cable🙂

 

[kings79]

Great thread!!! 🙂

What are on the middle 'thinner' wires? Any pinout Diagrams for the 4,1/5,1 PSU? Most I can find address 12v and are somewhat confusing.

Is there 5v on the smaller wires in between the thicker 4x GND and 4x 12v wires?

 

[HiroThreading]

.

Totally off topic question: how and where did you purchase that reference R9 390X card?

 

[h9826790]

Great thread!!! 🙂

What are on the middle 'thinner' wires? Any pinout Diagrams for the 4,1/5,1 PSU? Most I can find address 12v and are somewhat confusing.

Is there 5v on the smaller wires in between the thicker 4x GND and 4x 12v wires?

May be, but you don't need to touch those thinner cables. Simply follow this guide and you will be good.

http://thehouseofmoth.com/mac-pro-pixlas-mod/

 

[MisterAndrew]

Totally off topic question: how and where did you purchase that reference R9 390X card?

XFX sold one. I’m not sure why you’d want it though. Like an RX 580 performance-wise, but consumes way more power.

 

[HiroThreading]

XFX sold one. I’m not sure why you’d want it though. Like an RX 580 performance-wise, but consumes way more power.

Ah I see, I see. Thanks!

Yeah, I'm good now. A while ago I was looking for a reference 390X for my Hackintosh. 🙂

 

[lilins]

Totally off topic question: how and where did you purchase that reference R9 390X card?

ebay 🙂

 

[thunder72fr]

Where can i have got a Open-End to Dual 8 Pin (6+2) PCI-E Sleeved Cable (70cm + 10cm)? A reference?

 

[h9826790]

Where can i have got a Open-End to Dual 8 Pin (6+2) PCI-E Sleeved Cable (70cm + 10cm)? A reference?

You can buy any cable and just cut out the connector.

 

[thunder72fr]

Have you a reference with 70 cm mini?

 

[h9826790]

Have you a reference with 70 cm mini?

Sorry, not from me. I just pickup a whatever cable available from toolbox, cut a connecter, then use it for the Pixlas mod. There is no requirement to use 70cm cable. As long as the cable is long enough to finish the mod. You can use whatever extension cable you want to make it longer.

This is what I've done. Not the most tidiest setup (can't see it normally anyway), but work, and very easy to get whatever setup I want via some short extension cables.

 

[joemgill]

Did anybody ever get around to just making the extension cable between PSU and Board with the splices in it? I have a bunch of 4 and 5,1 Cheesegraters I need to do this for, and I think several have dying PSUs, so I'd like to use that cable to make PSU swap easier. I will need about 30 of the cables.

 

[Macschrauber]

1.1 to 3.1 is easy in that way, 4.1 und 5.1 is simply not doable as you cannot buy that Connectors. There You might solder cables to the Logic Board 12V pads. I dont think I would do that but thats your turn...

 

[Pressure]

1.1 to 3.1 is easy in that way, 4.1 und 5.1 is simply not doable as you cannot buy that Connectors. There You might solder cables to the Logic Board 12V pads. I dont think I would do that but thats your turn...

It seems like a normal molex connector. Pretty much like this one. Also the female connector might be 46436-1241.

Will have to pull my own PSU out back home and confirm.