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Prince134

macrumors 6502
Original poster
Aug 17, 2010
338
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I started a thread that I powered two down-clocked HD7970 to beat Mac Pro 6.1 3 years ago. At that time I used only dual on board 6 pin to dual 8 pin + 2 sata -> dual 6 pin for the 2x HD7970. It works because those two cards were down-clocked. 3 years later, I still see full potential of the machine (since 2009) that can beat nowadays' Hackintosh in this small, cute, military grade, Mac Pro tower with triple Titan X. Mac or Windows wise. If Volta won't be available for Mac Pro any time soon (I still hope it will), this is probably the most powerful setup we can get.

System:
Mac Pro 5.1 (2010)
Dual X5690 3.46Ghz
96GB RAM 1333Mhz
Titan X Pascal
Titan X Maxwell
GTX 1080 Ti
1 bootcamp 256gb in optical drive space, 1 ssd MacOs 10.12.4.

Without spinning 3.5" HDDs, Pixlas mod can be safely running 2 Titan X since the mod let the dual cards runs from the 12V rail from the PSU directly. To be able to run additional Titan X, an external power to power the third card is needed. I found xbox 360 first 2 generation PSU (exclude the slim) is easy to work with (203W or 175W). This PSU selling everywhere (gamestop, ebay) for $10-15. And it's easy to work as long as you have a multi-meter, a solder iron, and a few of heat shrinks. So I decided to have it a try. Here are what I did:

Open the 980W PSU, make a pair of 125V (AC) and 12V leads. The soldering job took a little time with regular solder iron, like the other guys said in the discussion. But it can be done with patience. This picture shows the 125V parallel pair leads.
Screen Shot 2017-04-28 at 12.07.13 PM.png
Screen Shot 2017-04-28 at 12.07.59 PM.png



Here is the Xbox 360 Power supply to put additional 175-203W 12V power to the 3rd GPU.
Screen Shot 2017-04-28 at 12.09.42 PM.png



Test it from outside first. Later I put it into the empty optic drive 5.25" space and conceal it nicely.
strand all yellow together as +12V, and all black as GND. leave the red (5v) untouched. The blue line is the switch on signal line, when you feed with Mac Pro's onboard 5v, it engage the 12V from the PSU to your GPU. In the photo it shows I used the 5V from the SATA power. Similarly, when you turn off the MacPro, it turns off the extra PSU in such same way. (don't be fooled here, the pink wire here is blue from xbox PSU).

Screen Shot 2017-04-28 at 12.10.27 PM.png
Screen Shot 2017-04-28 at 12.09.18 PM.png



Now to put it into the optic 5.25" drive space, I take the xbox 360 power's cover off, unplug the fan of the PSU (I don't need it, and I want it be silent, too). Before put it into the space, make sure you lead the wire from the right side so you get easier to drag the compartment. I did purchase a 5.25" empty plate to fit the PSU nicely (in fact with my bootcamp SSD in the same space as well).

View attachment 697805
Screen Shot 2017-04-28 at 12.12.50 PM.png


Up to here. My onboard 12V pool power from the 980W PSU, and the extra 175W PSU is ready. Now there is one magic product I want to share with: the EVGA power link:

http://www.evga.com/articles/01051/evga-powerlink/

Amazon selling it $9.99
https://www.amazon.com/EVGA-PowerLi...qid=1493419066&sr=8-1&keywords=evga+powerlink

What it does is to provide different angle for your GPU connector. I found it's wonderful because of two things: 1, it transform single pair of 12v+GND to dual 8 pin with internal handling of the pin layout, ie you feed with 12v it give you direct 8+6 to your cards, period. 2, it include power conditioning with two capacitors as shown here:
Screen Shot 2017-04-28 at 12.10.58 PM.png


The end result shows a neat cable arrangements. The SSD shown in photo with case taken off. It's easy and securely plugged in.
Screen Shot 2017-04-28 at 12.11.27 PM.png


Screen Shot 2017-04-28 at 12.13.25 PM.png


Since Titan xp is too expensive, I have ordered a 1080 Ti coming instead, and I will post update when it runs together with my existing 2 Titan X. Hope you guys enjoy it.

You know what, how I wish the next Mac Pro 7.1 use the same case design as mac pro 5.1. It's so much fun with versatility.
 
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Did you take the case off your SSD and mount it bare to the backplane? Haha. I once raided two macbook air blades in SATA adapters like that. Interesting mod, same for that evga item. Cool! Thanks!
 
Did you take the case off your SSD and mount it bare to the backplane? Haha. I once raided two macbook air blades in SATA adapters like that. Interesting mod, same for that evga item. Cool! Thanks!
Yes. It's mounted bare to the backplane. It's light enough without the case.
[doublepost=1493504600][/doublepost]Success!

Nvidia web driver +MacOS 10.12.4
Three cards: Titan X maxwell + Titan X Pascal + GTX 1080 Ti working together. Luxmark, Cuda z, Octane, Unigene 2 (superposition in windows) all are working excellent! After the mod, close the case, the Mac Pro 5.1 looks just the same as one without, since the extra 175W is in the second optic drive space.

Octane benchmark object file rendering at 94.6 ms/sec!!! If I could have put all three cards as Titan xp. I can predict the Octane benchmark object file rendering at 105-115 ms/sec!!! The Luxmark 3.1 should be scoring at 75,000s figures, as these benchmarks can almost linearly scaled.

Screen Shot 2017-04-29 at 1.16.30 PM.png


In order to put the 3rd GPU, all you need to do is to find this GTX 1080Ti or Pascal xp that without the DVI socket ie founder edition. The bracket need little job. But I bought an extra bracket from ebay for $8. to be used in this project and keep the original. Showing the following picture is one after change.



Screen Shot 2017-04-29 at 1.18.42 PM.png


Keep the original 1080 ti bracket, changed into this spare bracket from Ebay. Using a Dremal tool to cut a square slot like this, and I am able to put in the slot 4 and secure it.

Screen Shot 2017-04-29 at 1.19.00 PM.png


This is how it looks after you put into the slot 4. Rule is again the 4th slot fit with a card without DVI connector like Titan xp or 1080 TI.

Screen Shot 2017-04-29 at 1.18.17 PM.png




Octane benchmark object file rendering at 94.6 ms/sec.
Screen Shot 2017-04-29 at 1.17.18 PM.png


Supplimental photo for the 12V pooled source:
The 12V and GND soldering spots in the 980W power supply. The power supply has two PCBs. The 125V AC for the extra power and the 12V leads are from two separate boards. However, you will find room for the 4 wires fit and close the PSU case easily. As said, soldering need patience.


Screen Shot 2017-04-29 at 1.13.30 PM.png


Since the EVGA power link handles pin counts, all you have to do is the 12V and GND connection!

Screen Shot 2017-04-29 at 1.16.42 PM.png



A closer look how the EVGA power link handles the pin counts of the 8+6 pin, and why it saves wiring!!

Screen Shot 2017-04-29 at 1.17.04 PM.png


These two 8+6 was disassembled from EVGA Power Links just to make my connector look smarter. It's not necessary.
Screen Shot 2017-04-29 at 1.17.53 PM.png


Yes, I think this is the new king of mac (not quite but until I, or someone put in all 3 Titan xPs).
 
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-----------
Nvidia web driver +MacOS 10.12.4
Three cards: Titan X maxwell + Titan X Pascal + GTX 1080 Ti working together. Luxmark, Cuda z, Octane, Unigene 2 (superposition in windows) all are working excellent! After the mod, close the case, the Mac Pro 5.1 looks just the same as one without, since the extra 175W is in the second optic drive space.

Octane benchmark object file rendering at 94.6 ms/sec!!! If I could have put all three cards as Titan xp. I can predict the Octane benchmark object file rendering at 105-115 ms/sec!!! The Luxmark 3.1 should be scoring at 75,000s figures, as these benchmarks can almost linearly scaled.
------------
Luxmark score:
Screen Shot 2017-04-28 at 9.11.53 PM.png
 
Is all this power used just for Octane 3D or something else, like conquering the world?
 
Is all this power used just for Octane 3D or something else, like conquering the world?
Web browsing, email. etc... :rolleyes:

Lot's of other things: Windows gaming. One card meets all game requirement for me. BF1 for example. Yes, the Octane rendering, and video editing are what I mostly used for. FCPX in Sierra just disappoint me however. It's amazed this machine can handle 10,240 CUDA cores (11,520 CUDA cores if 3 Titan xP) in this well designed enclosure. This is also an ideal Multi-GPU machine for Deep Learning.

I haven't seen any eGPU box give you this much power. Not even 2 double wide eGPU support out there. Even if there is one can support 3 Titan X (I doubt the performance with TB bottleneck), I'd see it as big as one Mac Pro tower. That wouldn't be attractive.
 
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In theory, yes. But it doesn't look like it matter here. I have two cards in slot 1,2, and both are 16X pcie 2.0. The third card is in slot 4. which is 4X lane. Single card difference between slot 1or 2, from slot 4 can be only 0-3%. So rendering power is still almost linear, regardless pcie 2.0 x16 or x4 lane. We haven't really saturated PCie 2.0 yet.

I have no clue about the eGPU, if any one has 3 double wide eGPU setup, perhaps it can give answer. Barefeats tested two eGPUs not 3. My point is that if there is one would make it bulky, and make no difference of building a 3 GPU Hackintosh!
 
Borrowed another 1080 Ti from my friend. So it's 3 Pascal now. Working nice and stable. Things you can't see is that I have one 256GB SSD and the Xbox 360 175W PSU in the 2nd Optic drive space. One 1TB SSD naked on the SATA slot 1.

Screen Shot 2017-05-04 at 12.16.50 PM.png


Octane benchmark went up to 102ms/sec from 94.6ms/sec when a Maxwell switched to 1080Ti. Amazingly fast. If I remember correctly, single GTX680 was around 6-7ms/sec. Compute power is 15X more since 2012's latest Mac Pro 5.1 release. This is unbelievable since you can't see this much of delta with Mac Pro 6.1. (well basically no change, still D700 but it works better in FCPX, I know);)

Screen Shot 2017-05-04 at 12.17.28 PM.png


Here is the photo of the nice small switch to determine whether the extra power from the Xbox 360 175W PSU is needed. But don't be fooled. You don't have to switch manually to get the extra power. The switch is for with or without the 5v signal, meaning I would have switch it off if only two cards are on board. The 5v signal line for the switch is from the optic drive connection. I still have 3 SATA port to use (SATA3 SSDs all have to be naked:D, no choice:oops:). The extra power runs so smooth. You won't feel it at all (there was no fan noise on that). It's just like the Mac Pro 5.1 come with 3 pair of 12V aux power for GPUs.

Screen Shot 2017-05-04 at 12.16.36 PM.png


I wish if someone tried, let us know. Success, or issue, will be discussed here. Enjoy!:)
3 HD7970, RX580, any one? for FCPX?.:rolleyes:
 
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I can confirm Xbox One power supply will also work as extra power for your 3rd Titan X for your Mac Pro 5.1. Make sure you buy these xbox one PSU that's originated from Microsoft. This xbox one PSU not only smaller and lighter than the xbox 360 175w, the output current just higher on paper value. I haven't try the 16.5A version, but this 12V 17.9A version works perfectly. Keep in mind there are lots of 3rd party PSU on eBay that marks 17.9A output but when I took the case off, I decided not to try them because those parts are way too low grade than a genuine Microsoft PSU.


This version of PSU was tested great for your extra 12V source.
IMG_1210.JPG


It is shorter than the 175w for xbox 360, so it's easier fit into your optic drive space.
IMG_1211.JPG


Playing 2hrs of battlefield one were tested for both PSU on 1080 Ti at ultimate settings.
 
Funny to find this awesome thread! I was just testing a third Titan X (only Maxwell here) and wondering how to find a clean way to power it :)

I am confident doing pixlas mods, but this 360 PSU mod seems out of my league (can't solder well at all)
[doublepost=1495459500][/doublepost]
...

I wish if someone tried, let us know. Success, or issue, will be discussed here. Enjoy!:)
3 HD7970, RX580, any one? for FCPX?.:rolleyes:

Just for fun, beside the Titans, I tried three AMD 5770 but for some reason I couldn't get three to work! The Mac would just not start up.
 
Funny to find this awesome thread! I was just testing a third Titan X (only Maxwell here) and wondering how to find a clean way to power it :)

I am confident doing pixlas mods, but this 360 PSU mod seems out of my league (can't solder well at all)
[doublepost=1495459500][/doublepost]

Just for fun, beside the Titans, I tried three AMD 5770 but for some reason I couldn't get three to work! The Mac would just not start up.

Soldering is fun when you know certainly you can make what you want it to. It's like using fork and knife for steak. Whether or not the 2 gpu limit is because of the OSX? 2xD700 for Mac Pro 6.1? I don't know, but I can suspect.
 
Interesting - but also sad when there are off-the-shelf boxes that support 4, 5, 8 or even 16 Titan X class cards.

At what point do you realize that the classic Mac Pro is a square hole and you stop trying to pound square pegs into it?

View attachment 700676

Four Titan X (Pascal) off the shelf.

holy crap that looks hell powerful, anyway to Hackintosh the beast?
 
Interesting - but also sad when there are off-the-shelf boxes that support 4, 5, 8 or even 16 Titan X class cards.

At what point do you realize that the classic Mac Pro is a square hole and you stop trying to pound square pegs into it?

View attachment 700676

Four Titan X (Pascal) off the shelf.

Haha.. not yet. It's fun to have 3 titan X with Mac Pro 5.1 running OS X Sierra 10.12.5 and windows 10. This is definitely something that Hacintosh can't provide as smooth as it is. I have experienced struggling with NIC and audio drivers when I don't have a motherboard that's really working OOB.

Unless the one in the photo can run Mac OS, this is not at the same league either. And even if one can run with it, I wouldn't spend money on it while I can use the Mac Pro 5.1 on hand that give me both world with 3 Titan X capability. In fact, 4X titan X is supported (yes 4 of PCIE slots) if serious one should try Mac Pro 5.1 as deep learning workstation.

Unlike nMP users who have no choice but stick to 2xD700... but they look for eGPU I believe. When talking about this. Wouldn't it to be agreed that it's the drawback of the nMP being unable to upgrade so as to inevitably leading people to seek eGPUs. What a shame!

My last purchase of a Mac Pro 4.1 only spent me $400 (like new). With that price none of a Hacintosh is attractive At all. That's why I share detail of the mod for those that wanted... And for the most part, I think I am one that is the same as you guys who wish the so called mMP will be much more future proof just like Mac Pro 2009. For 8 years still upgradable.
 
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This mod is the best of all worlds. I built your 2 x HD 7970 mod. In fact, I bought the actual GPU's that you linked to on ebay as an example. Great Job! ...Thanks
 
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I wish if someone tried, let us know. Success, or issue, will be discussed here. Enjoy!:)
3 HD7970, RX580, any one? for FCPX?.:rolleyes:

I have two rx 580's... Only installed one yet, but I can install the other one and try some benchmarks if you're interested? Any recommendations?

Best regards, Daniel
 
Tell us BruceX test result with dual RX580. Also Unigene Superposition benchmarks: 1080P extreme, 4K optimal, and 8K optimal please.
 
Tell us BruceX test result with dual RX580. Also Unigene Superposition benchmarks: 1080P extreme, 4K optimal, and 8K optimal please.

Apart from FCPX. You mean benchmarking in Windows? I think MacOS can't utilise more than one GPU for superposition benchmark.
 
Apart from FCPX. You mean benchmarking in Windows? I think MacOS can't utilise more than one GPU for superposition benchmark.


I think you are right.
Or at least the Beta I'm running isn't fully optimised for the 580's yet. Haven't done any Kext-editing or what the proper terminology is.

I did the BruceX test with dual 580Rx installed. It took from 25 to 29 seconds. :( With a single 580 it only takes 21-22 seconds.

The beta doesn't recognise the 580's, I get the default "Ellesmere" device names. (My cards are from Asus)

From what I understand these results are rather mediocre?
I only intend to use this cMP for editing in Final Cut, which needs OpenCL-cards... But I actually hoped for better results then this... Our nMP at work does the BruceX in 22seconds, and my goal is to beat that machine. But I haven't had time to upgrade CPU and Ram yet, so maybee that will help out with the rendering in the future.

Best regards - Daniel


Ps. I noticed the Gpu's only worked 50% each during the Luxmark-tests, so the OAbout This 5,1.png Card.pngLuxmark.png Lazy 580s.png
[doublepost=1499816728][/doublepost]
Tell us BruceX test result with dual RX580. Also Unigene Superposition benchmarks: 1080P extreme, 4K optimal, and 8K optimal please.

I'm currently not running Windows yet.
If I can get the dual 580s to "work properly" for my editing in MacOS, I'll probably get another ssd for a Windows install. But I did some other benchmarks, that from what I can understand, wasn't very good. But I'm just getting started, so hopefully I can get the 580s up and running abit more.

Best Regards - Daniel
 
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I think you are right.
Or at least the Beta I'm running isn't fully optimised for the 580's yet. Haven't done any Kext-editing or what the proper terminology is.

I did the BruceX test with dual 580Rx installed. It took from 25 to 29 seconds. :( With a single 580 it only takes 21-22 seconds.

The beta doesn't recognise the 580's, I get the default "Ellesmere" device names. (My cards are from Asus)

From what I understand these results are rather mediocre?
I only intend to use this cMP for editing in Final Cut, which needs OpenCL-cards... But I actually hoped for better results then this... Our nMP at work does the BruceX in 22seconds, and my goal is to beat that machine. But I haven't had time to upgrade CPU and Ram yet, so maybee that will help out with the rendering in the future.

Best regards - Daniel


Ps. I noticed the Gpu's only worked 50% each during the Luxmark-tests, so the OView attachment 708191 View attachment 708192View attachment 708193 View attachment 708196
[doublepost=1499816728][/doublepost]

I'm currently not running Windows yet.
If I can get the dual 580s to "work properly" for my editing in MacOS, I'll probably get another ssd for a Windows install. But I did some other benchmarks, that from what I can understand, wasn't very good. But I'm just getting started, so hopefully I can get the 580s up and running abit more.

Best Regards - Daniel

For pure FCPX, dual 7950 work extremely well. I own 3 cards so far, all of them can run stablely at 0.956V 800/1250MHz (standard clock speed). VBE7 (Windows free software) makes the ROM extremely simple to edit.

With this little firmware mod, each card can run with a single mini 6pin supply. And draw up to around 140W (max, stress test), usually peak at around ~110W in FCPX (4k video rendering with 3 filters), and most of the time stay below 100W during video editing. Since this power draw includes the PCIe slot power. So, it's actually very OK and only occasionally draw more than 75W from a mini 6pin.

With this config, BruceX can be done in 15s (single CPU, W3690). By considering the 7950 is so cheap now. It's actually a very good cost / performance ratio option.

The down side, 7950 is a very old card now. And quite a bit of them was mining card, buying them 2nd hand with no warranty may end up gives you some headache. Also, it's limited to 3GB VRAM.

The new cards should have better power efficiency, however, that's based on stock voltage / clock. The new card is much harder to fine tune the VBIOS (voltage table is more complicated). With this voltage mod, the 7950's FCPX efficiency actually comparable to the new RX card (or even better due to mature driver support).
 
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