Okay, let's see if I can remember what's in my system first..Asus P4C800E DeluxeP4 3.0 Ghz w/ factory fan1 GB Crucial DDRAM 400mhz pc3200 2x512ATI Radeon 9800pro AIWWestern Digital 120 serial ATA HD 8mb bufferKhypermedia 52x24x52 CD rwMagic Spin x8 combo DVD rw / CD rw, + and - on all400 watt power supplyXP homeCTX 17" 1600x1200 CRTHD is on SATA connectorCD/rw is on Primary IDEDVD combo is on Secondary IDENo changes made at the time it started doing it.Problem:Now and then... no certain timing or cause... and goes long enough between that I forget about it.the system will fail to see one or both of the cd/dvd disk drives.Nothing I do will find them or fix the problem while the system is up.. "add new hardware" does nothing to help. Either does rebooting the system.I have to shut it off, unplug one or both drives, boot up, shut down, plug a drive in, boot up, shut down, plug the other drive in... and then things are fine.Now if I miss seeing that any drive is missed when it's booting, I know something is wrong when the system has the "hickups" that is,it has timed pauses in action.For example, if you move the cursor slowly across the screen, it will pause for a split second and then let you go another couple of inches and do it again. Same if you are typing etc.If I look at the "performance" window when this is happening, I see the CPU is using about 20% at rest, where it normally uses only about 2% just at the desk top.Have you seen this ? Known problem ? Thanks for any input,

Sounds very strange - did you check for viruses/spyware? The high CPU usage suggests something else is running...Cheers,Gosta.http://www.hifisim.com/images/as2betateam.jpg

Yeah the high CPU usage suggests a virus or something similar.

The higher CPU % is ONLY when it can't find one or both drives.. as soon as it sees the drive, it drops right back to 2% nominal.

Motherboard drivers maybe? It's obviously doing something, so maybe the drivers are corrupted.Cheers,Gosta.http://www.hifisim.com/images/as2betateam.jpg

>Motherboard drivers maybe? It's obviously doing something, so>maybe the drivers are corrupted.>>Cheers,>>Gosta.Well, the drivers work fine after it finds the drives though, if they were corrupted, they would stay that way...wouldn't they ?I'm not reloading drivers just letting XP use the ones it has on HD each time I plug and unplug the drive. Plug and play sets things back to working again.Thanks for the additional input :-)

I would update your chipset drivers for the motherboard, there are some known issues with XP and CD drives going missing, check the microsoft knowledge base. I would also try a different plus on your power supply incase there is a short there. How many watts is your power supply?