Does system memory affect video memory?

[klmico]

This is a bit of a n00b question but I was wondering if my system memory (512mb PC2700 Samsung on generic PCB) affects the memory on my video card, a PNY GF4 Ti4400. The reason I ask is because I always seem to be limited in my memory overclocking. I can get my card to run at 310/650 but there are major artifacts. I'm only leaving it at 300/600 because that is the highest I can seem to go without artifacts. I'm not sure if it's because the video card is a bad overclocker or if it's because of my bad system RAM. I had an OEM Radeon 8500 in my machine before the 4400 and I was only able to overclock my memory 10 mhz before I got artifacts. Any info would be helpful, thanks.

 

[Kaiser__Sose]

it's the ram on the vid card.