Using 2 PSU's to SLI GTX 460's

[Mutt]

I've got access to a Antec Truepower 550w PSU and a Palit GTX 460 1gb for a few weeks. I already have a Truepower 550w and a Gainward GTX 460 1gb in my system. Because my PSU probably doesn't have enough power to run a pair of GTX 460's in SLI can I add the second PSU to my case and run the other GTX 460 off that? The second PSU would ONLY be used to power the Palit card.

Like I said, I've only got this extra PSU and graphics card for a short time so I'd like to try a bit of SLI (for the first time) now that we have BF3 in the world.


Cheers

 

[vertica]

It certainly is possible to do that. The neat way is to find a dual psu 24pin atx adapter like they supply with the silverstone tj07 case (you may be able to buy this as a spare part) or make one up yourself. The free way is messy - connect your main psu as normal and the second one only to the gpu. Use a paper clip or similar to jump the green wired pin on the second psu's 24 pin connector to any of the black wired pins to start and keep the psu running. Then start the other psu as normal (the on button ).

 

[Hyburnate]

It certainly is possible to do that. The neat way is to find a dual psu 24pin atx adapter like they supply with the silverstone tj07 case (you may be able to buy this as a spare part) or make one up yourself. The free way is messy - connect your main psu as normal and the second one only to the gpu. Use a paper clip or similar to jump the green wired pin on the second psu's 24 pin connector to any of the black wired pins to start and keep the psu running. Then start the other psu as normal (the on button ).

http://www.overclockers.co.uk/showproduct.php?prodid=WC-021-OK

 

[Mutt]

Forgive me for being a bit dense but does that mean both PSU's will start up at the same time?

 

[Hyburnate]

Forgive me for being a bit dense but does that mean both PSU's will start up at the same time?

No you'd have to turn on the psu at the back when you want to power on the graphics cards.

 

[MooMoo444]

It certainly is possible to do that. The neat way is to find a dual psu 24pin atx adapter like they supply with the silverstone tj07 case (you may be able to buy this as a spare part) or make one up yourself. The free way is messy - connect your main psu as normal and the second one only to the gpu. Use a paper clip or similar to jump the green wired pin on the second psu's 24 pin connector to any of the black wired pins to start and keep the psu running. Then start the other psu as normal (the on button ).

Do not try this at home

 

[Mutt]

I don't think I will try this at home. I might have done if the PSU and video card had been mine. Best to play it safe.

Thanks for answering the question though Hyburnate.

 

[Mutt]

Just need to get this straight. Should I be powering on the psu which is running just the Palit card first and then turning on the system?

 

[sir-les-mp]

If you cant find a dual psu cable then the only other safe way to do it would be to make one from 2 x 24pin psu extension cables

Remove all the wires from one of the extension cables except for the green and the back wire beside it (pins 13 & 14) if i remember correctly
Also remove the male end from the cable.

Then carefully remove pins (13 & 14 ) ie the same green and black wires from the male end of the second extension cable.
Solder the 2 green wires to the same pin and then solder the 2 black wires to the same pin.
Carefully replace them correctly back into the male end of the second cable and when done you have a Dual PSU cable.

This way you will not overload or short out the second psu as both will have the correct load to switch on properly from the power button and will also shut down properly as well.

with the second psu i would also consider adding any system fans you have that do not attach to the mobo. Alternativley you could spread the power load evenly between both psu's thus extending thier life.