Help with running 3 cards off of 1 PSU

[aseldon]

Hello everyone,

I am looking to expand my mining rig. Currently its has a 5830 and 6950 in it. My board will take another card but I am having an issue finding cables to power it. I have this power supply http://www.xbitlabs.com/articles/cases/display/10-1kw-psu-roundup_15.html (that site has the best pictures of what cables it takes). I am using all 4 of the 6 PIN connectors to power the 2 cards I have. The PSU does 1000 Watts at 85% so I believe it should be able to handle a 7970 too. Is there any way for me to use the 4 PIN PATA connectors to provide a 6 PIN and 8 PIN connection for the new card or am I out of luck? Thanks for the help as always.

[juggalodarkclow]

molex>6pin  http://www.amazon.com/HDE-PCI-Express-Pin-Molex/dp/B0041P73LE/ref=sr_1_3?ie=UTF8&qid=1335136394&sr=8-3

molex>8pin  http://www.amazon.com/ATX-Male-Power-Cable-Adapter/dp/B0063JYZVW/ref=sr_1_1?ie=UTF8&qid=1335136336&sr=8-1

[aseldon]

Perfect thank you! It looks like I would need some female to male adapters coming off the PSU, correct?

[Mousepotato]

Perfect thank you! It looks like I would need some female to male adapters coming off the PSU, correct?

According to the link to the PSU you provided, included with the PSU are:

• Mainboard cable with a 24-pin connector (47cm)
• CPU cable with a 4-pin connector (47cm)
• CPU cable with an 8-pin connector (48cm)
• Two graphics card cables with 6-pin connectors (48cm)
• Two graphics card cables with 6-pin connectors (56cm)
• Graphics card cable with an 8-pin connector (49cm)
• Graphics card cable with an 8-pin connector (59cm)
• PATA-CDROM cable with one connector (18cm)
• Two cables with three Molex and one floppy drive plug on each (43+12+12+12cm)
• One cable with three Molex connectors (43+12+12cm)
• One cable with three Molex connectors (28+12+12cm)
• One cable with two SATA power connectors (48+12cm)
• One cable with three SATA power connectors (49+12cm)
• One cable with two SATA power connectors which is plugged into the PSU’s PATA connector (48+12cm)
• One cable with three SATA power connectors which is plugged into the PSU’s PATA connector (48+12+12cm)
• One cable with three fan connectors which is plugged into the PSU’s PATA connector (28+13+13cm)

So I'd say just hang it off some of those Molex plugs that already come with it.

[DILLIGAF]

Perfect thank you! It looks like I would need some female to male adapters coming off the PSU, correct?

According to the link to the PSU you provided, included with the PSU are:

• Mainboard cable with a 24-pin connector (47cm)
• CPU cable with a 4-pin connector (47cm)
• CPU cable with an 8-pin connector (48cm)
• Two graphics card cables with 6-pin connectors (48cm)
• Two graphics card cables with 6-pin connectors (56cm)
• Graphics card cable with an 8-pin connector (49cm)
• Graphics card cable with an 8-pin connector (59cm)
• PATA-CDROM cable with one connector (18cm)
• Two cables with three Molex and one floppy drive plug on each (43+12+12+12cm)
• One cable with three Molex connectors (43+12+12cm)
• One cable with three Molex connectors (28+12+12cm)
• One cable with two SATA power connectors (48+12cm)
• One cable with three SATA power connectors (49+12cm)
• One cable with two SATA power connectors which is plugged into the PSU’s PATA connector (48+12cm)
• One cable with three SATA power connectors which is plugged into the PSU’s PATA connector (48+12+12cm)
• One cable with three fan connectors which is plugged into the PSU’s PATA connector (28+13+13cm)

So I'd say just hang it off some of those Molex plugs that already come with it.

Or check first to make sure them 8 pin graphic connectors are not the 6 + 2 pin type, if they are then you can add another card no matter what cable end it requires.

[twoBitBasher]

Some cards come with these 6pin to 4pin molex adapters, and for those cards it might be okay to use them if you don't try to take them from the same cable harness. My experience however shows that this can lead to some voltage loss. For example if I measure voltage from an unused cable while the system is under load and get 12.05v and then measure what the GPU is actually getting and get 11.4v. This can't be good for the card in the long run.

So make sure your most power hungry card is using the PSU's own 6pin cables and use the adapters on the weaker cards. The adapters I have seen only have one +12v line while the 6pin connector has three! So you just have two lines feeding the card the same amount of current as 6 do normally.