Need recommendations + a wee bit o' help

[Stevontoast]

Currently have an ATI5670 1GB.
Suggestions?
Price range: ~£80-£100 (Sorry Americans, no Newegg stuff for me since they are mean and don't ship to the UK)

Current System Specs:

Windows 7 Ultimate x64
Core i7 930 @ 2.80GHz
H60 Water Cooling for a lovely quiet room.
6GB DDR3 1600 RAM
750 Corsair PSU

Something to match those would be nice! Unless 5670 does match it... inwhich case forget it!

I prefer ATI because of the god damn annoyingness of kernel crashing on most of Valve's games.
Saying that, they mostly crash because of hl2.exe not responding but I digress!

My monitor is also kinda crappy so suggestions on one of those wouldn't go a miss either.
As with my screen I currently have a SyncMaster 2223NW.


What I need help with:

I do have a problem with my spare PC that it isn't working. Booting it up does nothing except provide me with a black screen and nothing else. I think the motherboard is completely dead but need evidence before I throw it out the window and get a replacement.

This is the motherboard that I think has died: This.

If there is anyway you can, you know, save that motherboard then do tell me so I can finally get it working again... if not, no harm in just buying a new one... it only costs £40...