I have a 3 year old Dell 4600. It has a 250 W power supply. My 9800 Pro just died. I replaced it with an old Geforce 4200 TI 200. At first my keyboard wouldn't work, but when the system was shut off and turned on, it would, but now my sound card is not being detected. Any ideas? My sound card has worked for 3 years... only after putting in the other video card did it have problems. My guess i the power supply because the 9800 pro was part of the original system and Dell probably reduced the power reqs on it(proprietary).