ASUS P4C800E-Del board. C drive hooked to Primary Master socket on the board, CD/DVD hooked to Secondary Master socket on the board. Both are the only things on the cables (only the one drive on each cable - no slaves - and only drive hooked to each of the sockets). Before the C drive crash, this is how it was hooked and setup and all worked perfectly. Replaced the crashed C drive, reloaded XP. Had a number of problems at first, like Win only recognized the C drive and the floppy but not the other drive or the CD/DVD, although they were shown in SETUP, but not in Win in My Computer or in Dev Mgr. Also in Dev Mgr, there were all yellow question marks on all the items in "Other Devices" such as the USB, and there was no sound, and it said there was no sound card. I had been successfully using the onboard sound. Also said there was no BIOS installed. Went thru the users manual, reset a number of the settings in various places, and things got better. The CD/DVD and the other drive were recognized and worked fine. But the yellow question marks remained in "Other Devices" in Dev Mgr and still no sound. But then on boot, it no longer said there's no BIOS installed. That puzzles me - like some of the SETUP settings that I changed had done something before the change so that the BIOS couldn't be found?? I downloaded the updated BIOS for that specific board off the ASUS website and updated the BIOS on the board with it. Went in per the instructions with no problem. I think it was the first restart after the BIOS upgrade where it gave some kind of error message on the CMOS. Didn't understand exactly what it was telling me. Anyway, went into SETUP and reset a number of things from Default to where I needed them for my setup. Then on subsequent startups, that CMOS error message didn't appear again. Now all the pre-crash drives besides the C are recognized again and work fine. (I've added another large drive for backup, which is shown on SETUP but not in Windows, but that may be becuz i haven't "installed" it yet with the install CD? Anyway - ) But, still no sound and all the yellow Q marks in "Other Devices" in Dev Mgr. I verified that the USB Setup is correct - all set on 2.0 and High Speed (manual says all ports are 2.0 hi speed), with AUTO for Legacy USB devices, and that the onboard sound is AUTO which is supposed to recognize when any sound devices are plugged in, i.e. earphones or speakers. Before, I had headphones in the front panel and a speaker system plugged into the back, into the onboard sound. All worked perfectly. Then, of course, the PCU fan quit so I had to quit working with it. I figurred with the new updated BIOS install that it might clear up those Other Device and sound problems, but doesn't seem to have done any good. Would I be better off reinstalling the original BIOS from the CD now that the CD drive works? I've looked all thru the board User Manual and can't find any clues. Everything worked perfectly before. Am I maybe missing something in SETUP? Maybe in the CHIPSET settings or something? Any ideas or suggestions? Thanks much!!