All right, I had to remove my PCI NIC card's bracket to get it to fit my crappy case, but now the stuttering is gone. I even seem to have gotten an increase in speed; my ping in CS:S just got lowered by about 10. Anyway, is there a way I could fix the onboard NIC? I know there are some settings I could tweak in device manager, but I don't know what to do. I don't really want to use a PCI card, especially one without a bracket. I paid for the onboard lan, and I want to be able to use it. Thanks to everyone who helped!