Display screen completely blurry - not showing anything?

[Ross Balfour]

First of all, sorry for the vague title. I couldn't think of a clear way to describe this problem in a few words.

I have never had any issues with my monitor, a Samsung S20A300N 21' - until one morning on boot up the computer didn't boot up correctly, and told me to undertake a restore as some software and hardware files may have caused a problem. This is the first time I had ever seen this error, but carried out the repair process, but I'm starting to fear there may be a serious issue within my computer, as the result after these repairs was a blurry screen where my log-in screen should be (as seen in image below)

I recently installed a new Graphics card - Radeon 7850HD - into my computer a few months back, and it has had huge success to my gaming experience, and I don't feel it should be an issue to this problem. I also cleaned out my case and motherboard of any dust, and also tried unscrewing the HDMI leads from both the graphics card and monitor, but to no avail.

If anyone has any suggestions as to what my issue could be, I would be extremely grateful!

My specs:

Intel Core Duo CPU E6750 @2.66GHz
3.00GB RAM
32 bit Windows 7 OS
HIS AMD Radeon 7850HD
Conroe 1333 dvi-h 2.0
CoolerMaster RP600W
Samsung S20A300N 21'
1600x900 @ 60Hz