Hello all I have an HP DC7900 Convertible Minitower. A Few days ago there was a power failure and the PC lost power for a few seconds. When i turned it back on non of the USB ports were working. I tried connecting several USB devices that used to work before but the PC just doesn't recognize them. It doesn't even tell me that a new device was plugged in. When i go to the device manager i see the USB root and hubs all listed. Here's what i did so far: 1. Unistalled/renistalled the USB hubs. 2. Downloaded and installed the latest Intel chipset and USB drivers from HP. 3. Reset the motherboard CMOS. 4. Checked all the cables in the motherboard. If it helps, i also would like to mention that the PC internal speaker and the built it one are not working as well. When i plug the headphone in the socket i can hear the sound but without it i can hear nothing, no sound out out of the external built in speaker. Any help would be greatly appreciated/
