Hi. I don't know if it's the right forum. I got a hardware issue. My computer has started screwing. When I booted I got a message about checksum being bad and options to change settings or load defaults. I got it few times, then it booted normally. Then after a while I noticed I have no network connection. The usb port suddenly stopped working. I connected the modem to another port and it worked. After reboot I had no network connection again. So ethernet is the only way to go. But the main problem is not usb ports. I have no sound since then! If I turn volume up or down, the volume bar in Debian doesn't fill at all, it's empty. Any ideas? And it's not a software problem. I have no sound on Windows either.

Check your BIOS. Its possible that for some reason your BIOS has turned off sound, networking and USB ports.

USB is enabled. It is working right now, but I don't know what about later. I don't see any option for sound card. It is integrated sound card. It's also not about networking, I couldn't connect because I was connected via usb.