I have a weird problem with my new Powercolor 6950 PCS+ (this is the one that ships with the 6970 gpu clock on the secondary bios).
It will not run on my PC in the 16x slot I just get a blank screen. If I put it in the 8x slot it works ok....

System as follows
Antec 300
Q6600 @3.0
MSI P45 Platinum systemboard
4GB OCZ Reaper memory
Enermax Modu 82 525W PSU
Mushkin 120gb SSD
WD 500gb HDD
2x DVDROM

Previously I hade a Gigabyte 5870 OC which worked ok, when I first fitted it everything was ok, then I came home one evening (it was about 3 days after I had fitted it) and the computer wouldnt boot I tried a few things (dropping the OC and tried both bioses) and eventually found it booted ok in the 2nd PCIE slot. So I have left it running like that.

Fast forward to this weekend repair/upgrade time..... bought

MSI P67 board
i5 2500k cpu
4GB Ripjaw DDR3 memory

Assembled it all same fault, the 6950 will not run in the 16x slot works fine in the 8x.

Swapped in my wifes 4870 works fine in both slots, put my 6970 in my wifes PC in the PCIE 16x slot worked ok (well booted up and windows didnt try gaming), her PSU is a Corsair HX520 .

Only thing left I can think off is possibly the PSU but I cant understand how come it works perfect in the 8x slot plays games without a problem etc (when it will be using a lot more power than when it boots up).

I also thought the new 6970 was slightly less power hungry than the 5870's.

Any other ideas

bios update for the motherboard?

Nope the board already has the latest BIOS also there is no OC on it.

1) Possibly the card is faulty.

2) Perhaps the card is not sitting correctly in the PCI-E slot. The back part of the connector on the card provides the extra 8 lanes. If the rear of the card is slightly raised contact may not be being made with the connectors in the slot.

Someone did this to their card to test it at x8 speed:



You can see they masked off part of the connector to reduce the card from x16 to x8.

Make sure the card goes in the slot properly or that that part of the connector isn't damaged.

I'll have a look at that the slot itself must be ok for the 4870 to have worked, I did look to see if it was seated ok and it appeared to be.

On the old board there was nothing to stop it seating correctly.

I would have thought if the 16x part of the connector was damaged it would still work in the top slot just it would only run at 8x but I will pull check it again for damage.

I still find it weird that I have got exactly the same fault with 2 totally different boards and the only commom denominator is the PSU and the graphics card.

Sorry to necro bump but was this ever resolved? I got the exact same problem with an MSI 6850 Twin Frozr.