My computer has frozen (hard locked) 4 times today. I have never seen it happen before on this machine. Prior to the lockup, the system was at 5 days of uptime, which I realize is not stellar, but it shows it had been working. The downtime was just an opportunity for me to dust off the inside of things and remove a failed cd burner. The cd burner was not replaced, as I had a DVD burner in there as well.

Before anyone asks, my system is NOT overclocked, and the memory timings are all relatively conservative. I have had this system for a year, with only minor modifications (added the DVD burner, added a new fan, etc.) No change to CPU/memory/video card.

The logfiles do not show any unusual activity that I see, other than a badblock or two on one of my secondary hard drives (shown by smartd). CPU Temps, as reported by 'sensors', hover around 52-55 degrees Celsius, which certainly doesn't sound like anything too high to me.

When the system locks up, it just completely freezes, screen unchanged. Mouse doesn't move. Not a single thing shows up in the log files. I'm currently running memtest86+, but as of halfway through the first pass, nothing has been found.

My system specs are as follows:
Motherboard: Asus P4C800-E Deluxe
CPU: Intel Pentium 4, 2.8C
Memory: 2x512 DDR400 (PC3200) Corsair Memory

I do wonder about my power supply: could a low voltage be causing a lockup? I do have 3 hard drives, 1 optical drive, and the above mentioned hardware on a 400W PSU.

Any thoughts on my lockups are welcome. I appreciate your time reading this.

More information: the computer ALWAYS freezes with the hard drive activity light on. Additionally, after some reboots the system will not detect /dev/hda (boot hard drive) and occasionally /dev/sda (SATA hard drive). I am wondering if this could be a motherboard issue. 2 passes of memtest86+ did not find any errors.

Was this removed burner secondary master (hdc)? If so, do you have another drive as secondary slave (hdd)? Having a slave without master is bad idea...

Currently, my primary master, secondary master, and secondary slave positions are filled for IDE. It had been the secondary slave, but I moved my DVD-R drive to that position.

Update: freezes DEFINITELY seem tied to IDE issues. I tried to use Knoppix to get into my system and it freezes during "Scanning for Harddisk partitions and creating /etc/fstab...".

Dodgy disk or controller then maybe. You could try unplugging everything but your hard drive. If that fixes it, you've narrowed it down to something on the secondary IDE channel. If it's still broken, then probably either your hard drive is bad or the controller is bad.

Well, all the errors I'm getting actually are pointing to primary disk controller. Lots of /dev/hda errors when booting from a CD. However, running a S.M.A.R.T test on that hard drive will either be aborted with a "host reset" or will run to completion with no errors found: so I'm not feeling like it's the hard drive, but I kind of hope it is.

I'm going to try switching the primary and secondary IDE channels later and see if the problems stay on the primary.

I think I have solved my problem... seems it was a bad IDE cable. The cable actually was 24" long... not the 18" I thought it was. I replaced it this morning and have had 0 problems since then. We'll see if it stays that way.