Hardware Canucks

Hardware Canucks (http://www.hardwarecanucks.com/forum/)
-   Power Supplies (http://www.hardwarecanucks.com/forum/power-supplies/)
-   -   Running Dual Power Supplies (http://www.hardwarecanucks.com/forum/power-supplies/35693-running-dual-power-supplies.html)

CroSsFiRe2009 August 29, 2010 07:26 PM

Running Dual Power Supplies
So I'm lucky enough to be testing out 2 of the MSI 465 GE's that have been unlocked to 470's. However my power supply, a Corsair 450VX 450W(obviously) isn't able to output the power needed by 2 of these cards. Boots up fine with both cards and I can game with it but once in BC2, furmark, the second card goes into 2d mode after a few seconds. As I only have these 2 cards for a few weeks, I wont be getting a new power supply so I was wondering if its possible to run dual power supplies without using a dual psu adapter.
I have an OCZ 500W StealthXStream(yes I know, its a cheap unit but it'll do for now). I know its possible to hook the ocz up to one 465 and the rest of the system to the Corsair with one of those premade dual adapters which I dont have. Is it possible to jump start the video card/ocz psu (with a paperclip?) and then start up the corsair through the normal case switch properly/safely and without damage to anything? My main worry is if powering on the video card and having a delay between when the corsair starts up is harmful. If not, is there a reversible way to make a diy dual psu adapter that doesnt damage the 24pin connector?

Zero82z August 29, 2010 07:36 PM

You can do that, but a better method would be to splice together the green PS_ON wires and a pair of ground wires from both PSUs.

_dangtx_ August 29, 2010 07:56 PM

the 'dedicated' psu must be on before mains goes on. also hook up some drives and old hdds to the molex just in case. a few fans on this one wont hurt either

now, if you tried both cards on that 450w powersupply, lets do some math


basically if you pulled those numbers under furmark your psu shouldve shut down.

0o0 August 29, 2010 07:57 PM

Did you get 2 from the sale yesterday and leave less for everyone else in line like myself?

MpG August 29, 2010 08:13 PM

The PCI-E power plugs from the second PSU only supply 12V power, so you'll need to load the 5V rail through some other means, otherwise you're not going to get proper voltage output.

Zero82z August 29, 2010 08:23 PM


Originally Posted by 0o0 (Post 422040)
Did you get 2 from the sale yesterday and leave less for everyone else in line like myself?

As the saying goes, the early bird gets the worm...

CroSsFiRe2009 August 29, 2010 08:51 PM


Originally Posted by 0o0 (Post 422040)
Did you get 2 from the sale yesterday and leave less for everyone else in line like myself?

Oh of course, I just did it to spite you since I saw your BST thread stating that you wanted one at the sale. If you even bothered to read, I only have the second card for a few weeks since its not mine.

Anyways, I was also under the assumption that my psu would have shut down when pulling that much power but evidently it doesn't. Furmark loads up and runs for about 15 seconds with both cards almost stabilizing their temps before the temp on the 2nd card drops back to normal and it goes back down to 2d clocks according to gpuz and rivatuner while the 1st card keeps running.

So all in all, its possible but I just have to add some other components on. Would 2 hard drives be enough on the dedicated power supply for the video card to put it under load properly? Also, is there any potential danger to this?

CroSsFiRe2009 August 30, 2010 05:06 PM

Quick update, it all works! =D Attached a hard drive to the ocz psu that was dedicated to the 2nd video card and the rest was connected to the corsair. Powered up the video card/ocz psu using a paperclip and then the rest of the system without a hitch.

_dangtx_ August 30, 2010 05:19 PM

i strongly suggest you do a proper jobbe with the humping, err,jumping of the psu. decent gauge wire, put a dab of glue or electrical tape to keep it secure. i speak from experience:ph34r:

Zero82z August 30, 2010 05:21 PM

The gauge of the wire is really inconsequential. The PS_ON wire does not carry a significant amount of current.

All times are GMT -7. The time now is 07:09 AM.