5punk

First off I'd like to say I've given up trying to work this out after seeing the performance difference being totally negligible. I have an Asus P8P67 Pro and a 6950R Twin Frozr III 2GB. This was a new build and I was able to boot up and install windows just fine. The day after it wouldn't work, I was getting the beeps for no VGA card detected, yet it would work in the secondary PCIE slot albeit at 8x rather than x16. So I tried another motherboard and got the exact same issue which I though it highly odd.
The thing is, it still performs above my requirements even at 8x (Toms Hardware ran a comparison not long ago about this and it's like 1-2% difference). Aside from just saying 'the card is faulty' anyone got any ideas?

Board-swapping fault finding as it may be, but have you tried another card? Might be some bit of gubbinry that's only used in the 16x slot. If the fault's still there it's either a software issue of some kind, or some weirdness like PSU voltage or a BIOS setting.

/clutching at straws

I have got a cheap £15 card on the way purely for this fault finding. My PSU is a Corsair TX 650 so perhaps could be the issues. Be odd if it was software as it won't even display the bios when in the 16x.

Yeah, not software then. The only thing that loads before the BIOS is the video BIOS, so if you've got some sort of video hardware issue that's going to happen. I probably should have realised by the fact you got the video beep. Not that my advice is comprehensive by any means, but the card is where I'd be looking given what you've said.

If it's not a bios issue, and does it on different boards, I'd say it's a faulty card.

After all, if it's marked for being 16x compatible but isn't working in mulitple 16x sockets, then it's the card manfacturers fault.

Aye it does point towards the card, being the lazy kind though I really cba with the RMA of it. It's an MSI so it's got a 2 year warranty anyway if I get fed up but after seeing the real life performance figures, I thought it wasn't worth the effort.