I have a Dell 4700 with 2-256 MB RAM strips.  The machine's owner says he installed a NORTON SOFTWARE update, after which the BSOD appeared.  The machine will boot up in Safe mode, but within a few seconds, the BSOD again appears.  I ran a hardware diagnostic, and found that one of the RAM strips reported as defective.  I took this strip out, but the machine still has the same symptoms.  I intend to try to do an XP repair operation.  In the meantime, perhaps you hardware experts out there may be in position to confirm or refute my hypothesis that the defective memory strip may have caused read/write errors which in turn led to the BSOD.  If so, it appears these errors may be so extensive that I'll have to do a clean reinstall of XP.  By the way, after removal of the defective memory strip, the hardware diagnostics reported no errors.

Another by the way - My first step was to check for viruses and spyware.  Found no virus indication, and only a couple of benign tracking cookies in this process.  I also ran chkdsk, and found that two sectors had indexing errors, which were corrected.  Still - the BSOD continues to appear.

Any advice on this issue will be much appreciated.Although not very common any flaky hardware issues from power problems to failing HDD's and even numerous RAM based errors can in fact affect any software installed including the OS itself.
Although i don't think this may be the issue here it's better to be safe than sorry.
I'd suggest replacing the RAM first off because XP will gasp with just 256 in there.
After that i would DLoad and run the diagnostics on that HDD from the manuf. site.
Third i would post back here with the PSU manuf. and wattage rating so we're sure it's not underpowered.

Last but not least you could do a repair install of Windows if the blue screens CONTINUE after all this.Patio:  Thanks for your reply.   Since I couldn't locate new RAM right away, I simply removed the defective strip (after checking all the RAM thru several diagnostic tests), and MADE do with the remaining 256.  To free up as much memory as I could, I disabled all non-Microsoft startup processes, and managed to do an XP repair, but, as you suggested, it was a bear with so little RAM.  I have a GB of RAM on order now for this machine.  The hard drive passed all diagnostic tests, and the machine is only about 4 years old - so I gather that the continued blue screens after removal of the bad RAM resulted from corrupted files caused by the memory errors.  Anyways, after the repair operation (which I could not get thru until I removed the RAM), the machine is  stable and it appears it will do quite well when the RAM which I have on order is installed.

Thanks again.Good news indeed...stop by anytime.