Modular PSU for late 2009 Mac Pro? (dual 5870 cards)

revelstudios said:

This is the modular PSU I believe they used:
http://tinyurl.com/24n8vcd

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Yes, it will work (the optical bay will hold a standard 5.25" device, which is what this particular PSU was designed to fit).

revelstudios said:

Perfect! Thank you for clarifying. I just ordered that 5.25" bay PSU from NewEgg.com along with two of the 5870's from the Apple Store. Hopefully, by late next week, I'll have the rig up and running and will post results.

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I wish you luck (can't recall if anyone's tried the Apple branded cards with Crossfire under Windows, but I seem to recall that they do have the connection there; I just hope it's functional).

nanofrog said:

(can't recall if anyone's tried the Apple branded cards with Crossfire under Windows, but I seem to recall that they do have the connection there; I just hope it's functional).

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ATI 4870 works in CF (yes, those are Apple cards. IIRC some driver update enabled that, it didn't work when 4870 came). Of course this doesn't mean that 5780 will

A CrossFire connector definitely appears to be on the Apple 5870:

http://www.flickr.com/photos/psx1510/5180791393/in/set-72157625277406323/

But since I've never used CrossFire, I'm just making an educated guess. It looks like the same connector on my 3870 Mac/PC Edition, which came with a CrossFire cable. Also, I'd have no way of knowing if it's functional.

I'm interested to know if this will work! But purely for the curiosity; no way would I need dual 5870's as of now.

A couple of people, including myself, have the parts on order to try this in the next few days. Check out this thread for updates:

https://forums.macrumors.com/showthread.php?p=11432951

I did this exact thing a couple of months ago for a 5870+5970 trifire set up, it's fun to do, enjoy!

Hellhammer said:

ATI 4870 works in CF (yes, those are Apple cards. IIRC some driver update enabled that, it didn't work when 4870 came). Of course this doesn't mean that 5780 will

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I didn't recall that the Apple branded 4870's did, but I've no idea if it's also the case with the 5770 or 5870.

So long as the connector is there on the PCB, I suspect it will, but not going to presume it will with 100% certainty without confirmation (the only true way to know, especially with Apple branded cards).

nanofrog said:

I didn't recall that the Apple branded 4870's did, but I've no idea if it's also the case with the 5770 or 5870.

So long as the connector is there on the PCB, I suspect it will, but not going to presume it will with 100% certainty without confirmation (the only true way to know, especially with Apple branded cards).

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Initially it did not work but when catalyst 9.11 drivers were released matthewrusso reported that crossfire worked under windows 7. I'm getting both cards today and really want to try crossfire but before I go ahead and order a second modular PS I want to know if this poses any danger to my system like can it short circuit and ruin all components. I don't get how the second power supply will work. When the computer turns off will it do so as well and when I press the power button on the mp will it start both ps at the same time?

ildondeigiocchi said:

Initially it did not work but when catalyst 9.11 drivers were released matthewrusso reported that crossfire worked under windows 7.

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I'd forgotten about that (not a gamer myself).

ildondeigiocchi said:

I'm getting both cards today and really want to try crossfire but before I go ahead and order a second modular PS I want to know if this poses any danger to my system like can it short circuit and ruin all components. I don't get how the second power supply will work. When the computer turns off will it do so as well and when I press the power button on the mp will it start both ps at the same time?

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It's simpler than a standard PSU (assuming you mean the 450W ePower unit sold on newegg for $20USD), so it's always "ON" when plugged into the wall (no power switch from what I can see on the pics). This won't hurt the system though (even computer PSU's aren't totally "OFF" when you shut the system down; think about the green and black wires that have to be connected to fire one up).

As per damage, it's possible, but the protection circuits on the graphics cards should keep any problems from reaching the backplane board; assuming the protection circuits in the little PSU fail, which will also help - OV/OC circuits). Odds of damage should be rather low at any rate.

nanofrog said:

I'd forgotten about that (not a gamer myself).


It's simpler than a standard PSU (assuming you mean the 450W ePower unit sold on newegg for $20USD), so it's always "ON" when plugged into the wall (no power switch from what I can see on the pics). This won't hurt the system though (even computer PSU's aren't totally "OFF" when you shut the system down; think about the green and black wires that have to be connected to fire one up).

As per damage, it's possible, but the protection circuits on the graphics cards should keep any problems from reaching the backplane board; assuming the protection circuits in the little PSU fail, which will also help - OV/OC circuits). Odds of damage should be rather low at any rate.

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Ok guys I received both 5870s. Already installed one and love it . Now I will be purchasing the 20$ modular power supply off newegg. The only question I have is do I need to buy a seperate SATA power connector so that it connects with the ODD one that is in the mac pro. I can't tell if it's supplied from the pictures.

Would this one Work:http://www.newegg.ca/Product/Produc...70312&cm_re=SATA_power-_-12-270-312-_-Product

ildondeigiocchi said:

Ok guys I received both 5870s. Already installed one and love it . Now I will be purchasing the 20$ modular power supply off newegg. The only question I have is do I need to buy a seperate SATA power connector so that it connects with the ODD one that is in the mac pro. I can't tell if it's supplied from the pictures.

Would this one Work:http://www.newegg.ca/Product/Produc...70312&cm_re=SATA_power-_-12-270-312-_-Product

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It's definitely hard to tell what's going on from the pics... All I can see, is the 4x (2x 6pin and 2x 8 pin plugs) for the power cables to the graphics cards, and one 4x pin (flat) connector on the far right (where I presume the power cord to the wall goes).

There may be another cable on the far left, but I can't tell for sure. I even tried to find a manual from ePower, but the unit's not even listed on their site.

But assuming the flat 4x pin connector is not for the AC cord, then it's likely a Molex power input to activate the +12V rails for the cards attached. Now if this is the case, you'd need one of these (no need to get power to anything else), or one of these if you do (neither preserve the data connection).

If you need to preserve the data connection, you will need to make a custom cable from available cables (How-To here). Just use a Molex connector instead of a SATA cable (or use both if you need to). Takes some effort, but it won't mess up any of the internals and leave your warranty in tact.

But no one's that used it mentioned anything about a Molex connector, so this is why I presume that connector is the wall AC cord.

But keep us posted, as that would be a good thing to know for sure.

I just ordered the modular power supply, the SATA to MOLEX power cable and the crossfire bridge. We should know within the next few days.

In this picture of the back of the PSU attached below, the connector on the left appears to be the AC input (three pin) and the connector on the right is a molex connector which is most likely used for turning this PSU on/off in conjunction with the main power supply. So as you suggest, one of these will allow you to run it in the optical bay...

VirtualRain said:

In this picture of the back of the PSU attached below, the connector on the left appears to be the AC input (three pin) and the connector on the right is a molex connector which is most likely used for turning this PSU on/off in conjunction with the main power supply. So as you suggest, one of these will allow you to run it in the optical bay...

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It does look clearer when blown up (AC would only require 3 pins, not 4, but more pins than are needed have been used before).

But if that is the AC input on the left, the 4x pin would be used to turn the unit On/OFF (definitely saves some power, and may truly be OFF via a relay when the Molex goes to zero V).

I do suspect this to be the case, but couldn't confirm it via a manual.

revelstudios said:

I just received the PSU today. The modular plugs are indeed very thick and that is contributing to the problems mentioned where other users have been forced to break apart their chassis to route wiring. However, why not simply swap the bundled PSU plugs for other ones? Other PSU's we've seen with modular plugs have flattened or smaller wiring bundles.

We're going to explore that option first -- hopefully remedied with a short trip to Fry's.

5870 cards not received yet.

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I just did this, easy as pie.

revelstudios said:

Looks great but as I'm on mobile atm, not recognizing the part you're showing. Mind clarifying? Sounds like a great solution.

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Sure sorry, it's the inside of the Mac Pro's case door, with a small section missing, meaning that you can run cable's outside the optical drive bay and down to the video cards.

neckarb said:

Sure sorry, it's the inside of the Mac Pro's case door, with a small section missing, meaning that you can run cable's outside the optical drive bay and down to the video cards.

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What I'm just simply not understanding is why you cut that part of the removable side door of the mac pro? How does that help in the routing of wires?

a

rtrt said:

well if you don't cut it then the wires get squashed between that piece that hasn't been cut and the shelf the psu/dvd drive is mounted on.

if you remove it there's a gap for the wires & no squashing.

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Yep exactly, it means you can close the case door without any problems, and without diassesmbling the entire thing to route the cables, this made far more sense to me, as after a while I decided to sell my 5970 to wait for the 6990 and so i just unplugged the cables and took them out, without having to take the entire thing apart again....

revelstudios said:

Great solution! Thanks. Just so I can repeat the same steps you did -- assume you (1) removed the side panel of the case, (2) removed all of the screws from the side panel to disassemble into two parts, (3) cut notch in the space shown, (4) re-assembled with screws. Does that sound right? If so, I'll definitely do this today.

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That's exactly what I did, no complex disassembly required