ASUS GTX 580 fit onto P5K?

nope. no way around that. You need a shorter card.

This might be a silly response but can you put the card in the blue PCI 16 slot at the top? (I'm assuming that you put in the card in the black PCI 16 slot)

^+1 The GPU is supposed to be in the Blue PCIe slot.

However, if you purchased a 3-slot ASUS GTX 580 then with top mounted SATA slots I would 'try' 90-degree SATA cables but it's still if'y if even that'll work. Worth a try...

I did put it in the blue PCI slot...will it work in the black PCI slot?

The Black is a x4 lane PCIe slot vs the Blue x16 PCIe slot; IMO the platform is bottlenecked enough; you'll lose more performance.

Use the SATA3 and SATA4 (black SATA ports) slots OS HDD and DVD ODD drives; otherwise try/get the 90-degree SATA cables if >2 SATA ports are needed.

Thank you for your help....

You are spot on...thank you!

http://www.tomshardware.com/forum/305229-30-replace-sat...

Argh duplicate thread