Good. Now, use a separate Ad-ware/Spyware scanner and do a complete scan of your system. The point is, you have to learn how to troubleshoot your PC. You said that you didn't have this problem with SHIV before, but now you do. Obviously, something changed between then and now, and, like retracing your foot-steps to find a misplaced item, you have to remember/figure-out what that difference is. Maybe, it's adware/spyware, maybe it's not. Maybe it's a change to your system settings or gameplay options. There's only so much that forum members can help you with, not knowing your PC in the manner in which you do.
It's possible that a single Virus Scan can miss something on the first try, so rescan your system a second time. This is something that even the Virus Scan companies understand.
There's a reason for the slowdown and if it worked fine before, you can get it to work fine again. Only a little time and perseverence can make the difference.
