Thanks for your input Doc,
The KB article describes the problem but indicates Win 2000. I am running Win XP SP2.
Also, the problem deteriorated to the point where reinstalling an image previously restored and functional no longer worked as it resulted in the same stop 44 blue screen. Having hit the "end of the trail" I am reinstalling everything from scratch as I have before in the past. I removed my SCSI and modem cards in case they are a conflict. Also have a USB Agfa scanner E52 that I thought may have been an issue, but I am not sure - they ceased making scanners shortly after I bought it. I updated the Bios on the ATA100 card on the machine too. Any other thoughts?