I recently upgraded my pc and those are the changes i made
Core 2 Duo E7400 2.8 -->Core i5 2500 3.3
Ati radeon hd5770 -->Ati radeon hd6870
4gb ram --->8 gb ram
asus p5qld pro --->asus p8h67-M pro
Everything works fine except that i sometimes get some flashing pixels or sometimes stay still until i put a window over them (different colors) on desktop(NOT in games) only desktop or when i watch a movie or a video on youtube....i asked the shop i bought the things from and
they told me it might be overheating or need a new psu or monitor..i send pc there to check everything but they told me everything is ok....I have done some tests that are on internet like changing background colour but i see those pixels once at an image and i can see that image 200 times and not get pixels...I can't explain it more specifically ...I hope i made you understand....any help would be appreciated