2 power supplies, one motherboard

[jjiimm_64]

Does anyone have a trick to get the 2nd power supply turned  on  as to power the 3rd and/or 4th card?

I have a 1200 watt power supply, but want to put 3 5850's on one mother board.

The only thing I can think to do is grab an old mother board, but then the old board might not be compatable with the 20 pin connector. ( my old boards are....well old.)

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[swusc2]

There is something you can do which is called a "Wire Trick" or "Paperclip Trick" or you can buy a "2 to 1 Mobo Power connector". If you Google it I'm sure you can find a guide exactly how to do it.

BTW next time you should probably direct your question to Technical Support Forum.

[BitCointransfers]

Jump the Green and the adjacent black wire together......PS will then run.

[jjiimm_64]

..  Thank you.. 

Yup, I should have been over in the tech...  I dont suppose I can move this 'block' of text from this 'chain' to the tech chain...  lol

[djex]

Here's what you need: http://www.burningissues.net/how_to/power/psu.htm . I haven't tried it but it should work.

[M4v3R]

Jump the Green and the adjacent black wire together......PS will then run.

This. I've tried it yesterday on my PSU and it works fine. Green wire is a Power On wire and you need to short it with any Ground (black) wires.

[trippp]

I've heard it is also important to connect the ground wires on the PSU:s, so they have the same ground level. Is that true? Do you need to do it even if you run both PSU:s off the same power bar?

[Soros Shorts]

I've heard it is also important to connect the ground wires on the PSU:s, so they have the same ground level. Is that true? Do you need to do it even if you run both PSU:s off the same power bar?

Once you connect the second power supply to a card that is connected to the PCI-e bus of the motherboard the 2 PSU's are on the same ground level. However, it is better to directly ground the PSU's together because the ground pins of the PCI-e bus are only rated for so much current.

[HudsonStan]

I have a 1200 watt power supply, but want to put 3 5850's on one mother board.

You can power 4x5870 with that 1200W monster. I have 2x5870 powered by 600W PSU, drawing 520W including PSU losses. Another PSU draw unnecessary power.