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AndreeOnline

macrumors 6502a
Original poster
Aug 15, 2014
711
505
Zürich
I'm creating a thread for my 4.1-->5.1 mod to keep everything in one place.

I will document my upgrade to X5690, PCIe SSD (Apple SSUBX) and PSU mod to allow for two modern gfx cards using only the internal PSU.

I have gotten my Mac Pro now (2x 2.26GHz) 4.1 from 2009. It had one Nvidia 120GT and one Nvidia 8800GT, 12GB ram and a few external scratches =) Price was $680 in March 2015.

I have ordered de-lidded X5690 CPUs that are being delivered. ($599 for package with dual de-lidded CPUs and thermal paste).
I have ordered a 1TB SSUBX that is being delivered. 1450 MB/s read/write with native TRIM. I got my blade from forum member Keter, who in our correspondence was friendly, quick to reply and basically shipped the SSD within hours. He is tapped in to the supply chain, so if you want a SSUBX specifically—check with him.
I have ordered a $10 PCIe adaptor for the SSD.
I have ordered 48GB CAS9 valueRAM 3+3 modules.

I already have a R9 280X 3GB in my current 5.1 3.33GHz 6-core.
I have an OWC Accelsior_E2 500GB card with external eSATA (currently a 1TB Samsung Evo 840 via eSATA)
I've got a bunch of hard drives.

----------

CPU upgrade, two Xeon X5690

I opted for de-lidded CPUs to save me the hassle. You can de-lid yourself and save up to $150. Check with forum member Box185 before buying from Ebay.

Upgrade firmware from 4,1 to 5,1. There is a very convenient tool out there and it is basically the click of one button. The tool explains the steps.

1) Download the EFI tool here. You need to be registered to the forum to see the file.
2) Just in case, download the Apple firmware update file here, then double click it to mount it.
Having this file mounted when you click the EFI tool will allow the EFI tool to grab updated files from Apple's newest archive and include them in the update process. That's what I did and I had no issues. Some people that just used the original tool (from 2011?) had problems.
3) Waiting for CPUs to arrive. In my case it's a drop-in procedure.
4) Here are Arctic Silver's instructions for applying thermal paste.

-----------

PSU mod:
After having opened up my Mac Pro I found four 12V lines and four GND lines leading out of the PSU. My plan of attack is now to splice into these wires (not cutting or soldering, but using industrial clips that are purpose made for tapping into power cables. By using a small plastic clip we can create an insulated bridge between two cables very easily. See this youtube video for reference: https://www.youtube.com/watch?v=WFdVkSaHRpU

I will then either create, or have created for me, a nice sleeved cable that splices 8 wires onto the PSU lines (12V+GND) that later splits into two 8 pin PCIe connectors. Like this:

Mac-Pro-2x8-pin-sleeve.png


I will then be able to take the two 8 pin connectors directly from the PSU (distributed over all four lines) and use the 6 pin mini PCie from the mainboard for additional power.

This should allow for two 2+8 pin gfx cards.

SpliceTap.jpg


UPDATE: I bought mine here on Ebay.

This little darling can be clipped onto a 12 awg wire, and then I can put a 14-18 awg wire into it, press the metal bridge down creating a connection, and then close the lid for insulation.

I will need to clip 8 wires in total to the 4 12V and 4 GND wires.

It's a clean solution that should work. If it does indeed work, I think this is easily the most approachable way to attempt this mod yet.

[UPDATED 17. April]

Here's the cable I got today, ordered from ModDIY.com, with the following description that they understand:

[open end, 10cm] ——— 70cm (sleeved)——— [8 pin graphics]— 10cm— [8 pin graphics]

IMG_3507.jpg


IMG_3508.jpg


The cable needed to be routed through this hole:

IMG_3510.jpg


That turned out to be a non-issue. I just taped the tip and threaded the cable on the first try with zero issues.

IMG_3509.jpg

IMG_3511.jpg


I needed to remove some tape around the original PSU cables to allow me to separate them a bit. After that came the fiddling of clipping everything on. I did the install in place, so there isn't too much room to work. You need a tool with decently long handles to allow you to clamp the splice connectors all the way down in the "box".

IMG_3515.jpg

IMG_3517.jpg


Even though the clips are somewhat bulky and hard to lay flat, there was room to install the optical bay without any issue. When pressed in, it doesn't actually quite reach the back plate.

A clean install:

IMG_3522_crop.jpg


IMG_3518.jpg


First test of running Valley on my 5870 has been successful. Will update when I've tried two cards.
 
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A few pictures:

2xTray.jpg


Still today, a tidy and beautiful design. Had this computer had its connectivity updated (Sata III, Thunderbolt, USB3), it would no doubt be very popular.

MacPro4,1.jpg


With two gfx cards and a SSD adaptor + USB3 I will run out of slots.

PCIeSlots.jpg


PSU.jpg


Unmarked black cables. To see what is what, you have to pry open the PSU and follow the lines to the PCB. They are marked at the base. The two outermost thick wire pairs are GND and the two inner most thick pairs are 12V+.

PSUcablesFlat.jpg


---------------- UPDATE end 2017 since I think this is an awesome look, featuring Vega Frontier Edition – 16GB RAM, factory overclock and 10-bit monitor support:

MP_Frontier1.jpg


MP_FrontierSpec.jpg


8 years later, this champ is hoping to be relieved sometime in the next year by a product of similar class and value. The AMD Vega Frontier Edition looks awesome here I think, but is probably going back for a final switch back to a Nvidia GTX 1080 Ti.

The Frontier is an interesting proposition on paper—splitting the worlds between gaming and production. But to reap all the benefits you'd need proper driver support. Still, it boots flawlessly into High Sierra, as many other modern AMD cards.
 
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Much of this has been covered, of course, but I still feel that it nice to have everything in one place.

I think the PSU project is something that could be a game changer if it goes smoothly. I'm talking to a cable modder to see if they can make the correct cable and then make it available for anyone to buy.
 
A splice harness like that would be pretty amazing, but I seriously doubt they will be able to find the needed connectors for the motherboard/psu socket setup.

Did you also notice that there are only 4 large pins going to the motherboard, 2 ground and 2 12v, yet there are 8 of the heavy wires. So apple used 4 wires each for ground and 12v, yet just combined them into 2 pins of each at the motherboard. I think our idea of combining the 6 12v and 10 ground for a pair of 8pin pcie plugs should be no problem provided the connections are properly done.

I do foresee a possible problem tho:
What if the amp load coming out of the PSU is measured at the PSU.. Meaning we will hit the 400-500watt overload = mac shuts off, even if our cables are wired directly into the PSU.
If the shutoff failsafe is measured from the motherboard somehow, then we should be ok since I hope it wont detect the extra current from the added in connectors.
 
A splice harness like that would be pretty amazing, but I seriously doubt they will be able to find the needed connectors for the motherboard/psu socket setup.

Did you also notice that there are only 4 large pins going to the motherboard, 2 ground and 2 12v, yet there are 8 of the heavy wires. So apple used 4 wires each for ground and 12v, yet just combined them into 2 pins of each at the motherboard. I think our idea of combining the 6 12v and 10 ground for a pair of 8pin pcie plugs should be no problem provided the connections are properly done.

I do foresee a possible problem tho:
What if the amp load coming out of the PSU is measured at the PSU.. Meaning we will hit the 400-500watt overload = mac shuts off, even if our cables are wired directly into the PSU.
If the shutoff failsafe is measured from the motherboard somehow, then we should be ok since I hope it wont detect the extra current from the added in connectors.

Well, one member here has already modified his PSU to do the same, and he reportedly has no such issues. I just figured a splice would do the same thing without the need to cut the factory wires, or hack the PSU. It would be much easier this way if possible.
 
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Hi, crjackson2134

you can see that my plan is already to go with splicing. But looking around I only found the little clip that I show in my post above. It means I will be splicing the wires individually, but I will still get the benefit of not cutting the wires or solder.

I see that as one of the most interesting aspects of this mod!
 
Hi, crjackson2134

you can see that my plan is already to go with splicing. But looking around I only found the little clip that I show in my post above. It means I will be splicing the wires individually, but I will still get the benefit of not cutting the wires or solder.

I see that as one of the most interesting aspects of this mod!

I can't wait to see the finished product.
 
Did you also notice that there are only 4 large pins going to the motherboard, 2 ground and 2 12v, yet there are 8 of the heavy wires. So apple used 4 wires each for ground and 12v, yet just combined them into 2 pins of each at the motherboard. I think our idea of combining the 6 12v and 10 ground for a pair of 8pin pcie plugs should be no problem provided the connections are properly done.

I do foresee a possible problem tho:
What if the amp load coming out of the PSU is measured at the PSU.. Meaning we will hit the 400-500watt overload = mac shuts off, even if our cables are wired directly into the PSU.
If the shutoff failsafe is measured from the motherboard somehow, then we should be ok since I hope it wont detect the extra current from the added in connectors.

Due to the layout of the PCIe graphics connector I will have to split 6 over 4, so it won't be perfectly distributed. But I still feel, with sheep666's testament that his setup works from a load perspective, and the assumption that the overload protection is measured against the 980W/80A single rail, that it will be OK.

Any spikes in power consumption with these cards seem pretty momentarily when I look at reviews with detailed effect charts.

----------

Good work !!!

Dual GPUs will become more common if this pans out.

Let's hope so! That is also what I am trying to say the cable modder: there is a opportunity here =)

But honestly, as these machines also approach end of life, those that remain will likely be pretty pimped out render machines. Many will use dual gfx.
 
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hands down to this guy andree you are the man! Good Job!
thanks so much for posting your knowledge and using your time.
i for sure will donate money for a beer or couple of them just for the info.
too bad mvc or 666sheep didn't think about selling something premade so there is more dual GPUs which i for sure im interested on.

By the way look at my post here https://forums.macrumors.com/threads/1859578/

so since i busted that little chip i would like to get all the energy directly from the PSU (2 6 pin cable and 2 8 pin cable, or it could also be 4 8 pin cable) do you think thats possible?

i mean a power supply of almost 1,000w i think should be able to handle that for sure.

btw i have 64gb ram and
1 x5690
1 r9 280x turbo duo power color (have not arrived yet, brand new 200usd)
1 5770
2 intel data SSDs drive 240gb and 120gb
1 TB rotation disk drive
I removed the CD drive bay to use less energy and free those 2 connectors

Thanks again!
 
I like it. Excellent guide.

Obviously you'll do this hack -EFI utility for 2009 MP [ http://forum.netkas.org/index.php/topic,852.0.html ] first before installing those wonderful de-lidded X5690 CPUs.

Yes, that is already done. It was one of the few things I could do (and wanted to check first before ordering everything) while waiting of for the components to arrive.

I will include it in the first post so that new readers that stumble into this thread don't miss that important step.
 
My friend and I successfully completed this mod on my 2012 5,1 tonight.

We installed one heavy style cable (16guage) for pcie 6pin. Then I used a 6pin to dual 6+2pin splitter to test it on my GTX 680.

Its working fine. The power draw is now showing on the "PSU 12V PSMI" sensor. It maxed out at 28 amps(336watts) while running Heaven which is all 12v draws combined, including the new vid card feed. When the benchmark ended, it dropped to 12 amps while idling in Yosemite.

I took pictures showing what we did, and will upload them tonight when i get them transferred off my friends phone. Soldering the cable to the PSU board pins was difficult, and the grounds didnt come out as neat as we hoped. My friend said the problem was his 140watt soldering iron wasnt hot enough for the heavy connections and lead free solder that apple used. The cable itself was also a major pain, as there is almost no where to route it down to the pci compartment. I ended up threading it up through the cutout used by the dvd drive power cable, then behind the fan, and into the PSU. We had to thread the cable, then solder it all together while it was threaded. holding the PSU by hand. It did come out very neat and tidy when finished, so was worth the effort.

I honestly dont know if the 16guage wires are heavy enough to support two full power 8pin on the single 6pin feed. That would be 100 watts per wire, on the 3 hot wires. But, feeding 66watt x 2 to the gtx 680 worked fine.
 

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My friend and I successfully completed this mod on my 2012 5,1 tonight.

Nice! Good to hear that you got it to work. I'm impressed that you managed to solder at the base of the PSU. I found it to be pretty tight.

I am still waiting for parts to show up here. I've lost time (and some patience) by dealing with a Hong Kong based cable modder. At one point it took two days to get a reply on an email, and then the reply didn't move things forward...

I think I have an order in place now that will result in a cable I can use. I am also using a split. But with the custom cable and shipping I guess I am looking at two weeks before I can implement this myself.

CPUs and SSD will be around a week out (estimating shipping). Everything went via family in New York and now needs to reach me.
 
My friend and I successfully completed this mod on my 2012 5,1 tonight.

Good work! You took a more difficult route (soldering directly to the plate), but if it works for you it doesn't make a difference. One thing I would pass on: using the splitter (other than made by myself/yourself). They usually use low quality wires – not the pure copper but some kind of alloy.
 
Some More pictures showing routing.

Now just need another evga 680 mac edition to test SLI on it !

Or a pair of 970 or 980 in SLI. :)

Hey MVC, need a beta tester for dual card setups? lol
 

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...and on a separate note I learned that DaVinci Resolve Lite (the free version I'm using), only supports one GPU. For DUAL GPU support I'd have to get the $1000 Regular version.

That sucks, since Davinci Lite is my main motivator for modding the PSU. Time to re-evaluate. Maybe I can get hold of it "used".

Might have to go with one powerful GPU now, instead of two "price performance" ones. But that kind of makes me want to wait for AMDs next release before jumping in. When is that, by the way?

I'm glad that we now have two points of confirmation that this mod works, as I still will probably need the 8-pins even if just a single card.

I'd happily do this mod, but it has to give me something in return. It's not just "to see if it works". I primarily want a stable workstation. And I might add: one that I feel safe about leaving rendering overnight without burning down the house...
 
This mod is still worthwhile for a single card.

As long as we dont run into any overload wierdness, this mod will easily provide a full power 8pin, along with the two built in 6pin. Since even a titan black needs only a 6 and 8, you could run one. Could really get crazy and run a titan z I think also since its two 8pin, you can join the two motherboard 6 into an 8, and use the extra cable for the other 8.
 
Yes, I feel I will do the mod.

But I had envisioned just dropping in a second 280X card for price/performance as soon as my stuff gets here. If I'm changing plans to go with one GPU, I'll probably wait for 390X and that means I won't do the mod until I NEED it.

It's simply a "don't hold your breath" for those following the thread strictly for the PSU mod. We'll see. Maybe when the cables get here the temptation will be too great... =)

All my 3D rendering is currently CPU based, otherwise that would have been a great reason.
 
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