Is this a 8-pin PCI-E?

[EXT64]

I was wondering if the 8-pin power connector on my power supply will work for 8-pin PCI-E. It is really the power connector for EPS/Server motherboards, but it looks so similar I had to ask. It is 12V, like a PCI-E. Here are the specifics:

Plug Layout:
8-pin MB power
[ ] <]
<] <]
<] [ ]
[ ] <]

6-pin PCI-E power
[ ] <]
<] <]
<] [ ]

As you can see, a six pin PCI-E could fit into the 8-pin's slot, which I assume has to be possible because the 2900XT can use either 6 or 8 pin connectors.

Connector Indentification:
8-pin
COM 1 12V 5
COM 2 12V 6
COM 3 12V 7
COM 4 12V 8

6-pin
12V 1 COM 4
12V 2 COM 5
12V 3 COM 6

I wasn't sure if it would work because the COM and 12V are opposite the six pin's layout. It seems to me that it wouldn't, since the polarity is reversed, but could you plug a 8-pin EPS into an 8-pin PCI-E and destroy your card? Or did they change the shape of the 8-pin so that this is impossible? Thanks for any input!

 

[Blackhawk44M]

I was wondering the same thing but then again it seems not to smart to put such a power hog on the same rail as your MB or 12V 4pin.I was wondering myself if they maybe realized how many people have that 8pin connector unused for the PSU.Cool that u thought the same maybe lol.

 

[EXT64]

Thanks,

It would have been nice if they had made the PCI-E 8-pin the same, but they can't be that practical. At least they made it so you can't plug the wrong plug in. And I see they made it so that 8-pin PCI-E is backward compatible with six-pin. I guess I will just use the 2x6-pin for my 2900XT build.

 

[Crashman]

Note that PCI-Express connectors are OPPOSITE POLARITY from ATX12V connectors. If it had worked, power protection would probably prevent it from firing up. If it did fire up, short circuit protection would shut it back off instantly. If short circuit protection failed, you'd have a nice little fire to deal with.

So it's a good thing it doesn't fit!

 

[locky28]

So 2x6-pin's will still run the 2900XT fine? Is the 6+8pin configuration only meant for O/C'ing?

 

[EXT64]

I believe that you can even OC with the 2x6-pin setup (however it isn't recommended by ATI), but ATI Overdrive will not work without the 8-pin. Oh well, for now I will just be satisfied with the over 2x performance increase over my current setup.