Bitcoin Forum

I'm looking to add one of the new 6950 cards into my machine which only has four PCIe connectors, all of which are 6-pin. The cards I'm looking at require a 6-pin PCIe plug and an 8-pin PCIe plug. They do seem to come with 8-pin to molex adapters which would solve the problem of no 8-pin connectors from my PSU, but I'm wondering if my performance would suffer as a result. Is there any real difference here? Will the power to the card be just as stable either way, or would it suffer without a true 8-pin connector? Would this also affect my overclock potential as a result?

when done right theres no difference (ignoring an insignificant loss in voltage due to extra connectors).

if its a multi rail PSU just make sure power draw is in spec each rail and try to load the rails evenly. if single rail try to load the connector strings evenly, you dont want 60 amps on one string for example.

4x 12v rails, so pretty much as long as the adapters go to molex connectors on seperate chains (i think there are three or four different chains of these, would have to check to be sure though) the power to the card will be virtually the same as if i had a regular 8pin plug from the PSU?

The molex adapter will supply whatever power the card needs, up to the limit where it catches on fire anyway ;)

Use the molex connector closest to the PSU to minimize electrical losses.  As long as your molex cables are a large enough gauge to support the power draw, and the PSU can supply it on that rail, you'll have no problems at all.

The extra pins in the 8pin connector simply add another 12V wire to "spread" the current draw and avoid burning up wires.

As long as your adapter/molex aren't getting hot, you don't have to worry about that.