Getting a black screen

[delielejdeath]

Since yesterday, infact now its happened two times, I just get a black screen and the pc hangs, what exactly is this problem?
And how should it be dealt with?
I've got windows 7 x64 ultimate edition(got it for the past year and worked fine)
core 2 duo 2.8ghz, 4gb ddr2 ram, ati raedon 5670 1gb, 1tb seagate 7200.12, 2 dvd 24x drives sata, and a 450W PSU
I previously had a 9400gt, recently got a 5670

 

[w7pro]

There are a few things that you can do to try quell this issue. The first thing I would recommend is to do a system restore. Unfortunately, there could be a myriad of issues that are causing this problem, but it's a good idea to try and rule out as much as you can. Microsoft also has a page on blue/black screens: http://windows.microsoft.com/en-us/windows7/Resolving-stop-blue-screen-errors-in-Windows-7

-- Ryan
Windows Outreach Team