Other than graphics card, what other piece of hardware can Cause artifacts/graphics problems/pixelation

For artifacts I would say the leading cause is overclocked or overheating VRAM followed by overclocked GPU followed by the GPU driver followed by System RAM.

After that, running out of or saturating system RAM can cause pagefile calls to happen to the hard drive which can manifest as stuttering, FPS loss or even pixelation & blury-ness ingame.
 

R0ckTillWeDr0p

Honorable
Jul 22, 2013
46
0
10,530
That's weird :S my ram is fine, hdd is fine as I've tested on two and run a clean copy on one, not the gpu as I've run off onboard and exact same problem, tried a different monitor/Cable, only thing left is cpu and psu, for some reason my cpu is really unstable under stock voltage so have to.up it to 1.2v