I recently bought a new PC. A Dell Ispiron 560 (3.2 ghz, 4gb memory, etc.). I don't want to get big into gaming on it I just wanted a better video card than the crappy one that came with it, so I bought a HIS HD 4670 IceQ 1gb ($60). Because of that I had to upgrade the PSU from a stock 150w to a OCZ Fata1ity 550w power supply. I uninstalled the previous video drivers by going into Device Manager and deleting them. I also used Driver Cleaner Pro. Then I installed and updated the driver for the HIS 4670. Now my computer seems to have minor mouse lag and the cursor plays catch up to where I want it to go. Also while playing some minor games (ex. A.V.A.,Genesis AD, TheHunter, Vindictus) it lags horribly and makes a grinding sound which comes through the speakers, it does this not only in a game but I can be surfing the web and listing to itunes and it will just spazz out making the grinding sound. Any help? Did I screw something up? I tried looking around on Google, but there were no resovled issues. Some were saying it could be a bad PSU or that there is a conflict with Micrsoft High Definition Audio Dirver. Added: I am getting really frustrated with this, I'm 99% sure it is through the speakers. I took out the HIS 4670 and went with the stock video card and it was still doing it, so I thought maybe it might have something to do with the power supply so I switched it back to the 150w one. The lag and noise still continues to happen I don't know what to do at this point. Everything is like it was when I got the computer. Could I have a virus/malware or something of that sort, or maybe it is the HDD.