About 2 days ago my original Xbox started freezing in the middle of playing Black Ops. I cleared the Cache and tried removing hard drive. I tried MW2 and Call of Duty and same thing happens with them. The games will load and start playing and then just freeze. However when I played Halo 3 I had no problems at all. I checked discs all are fine. It can't be a coincidence that just those games are freezing. Any ideas?