suspected HD failure, but not sure

If I'm posting in the wrong place, please direct me. Thank you.

My hard drive is acting strangely. I've troubleshooted it to two
encapsulating ideas:
a) it won't save any kind of change between boots (yes, i'm admin; no,
i'm not in safe mode), and
b) it causes a BLOD under varying conditions, all of which indicate
intensive HD reading or writing (stop code 0x0000008E; only legible
information is "ATAPI.SYS")

Details
----------
a) -hooked up a new monitor, every boot it searches for the driver,
finds it, installs it but it's gone next boot
-created new files on desktop, c drive, or anywhere but they're gone
after reboot. Even booting with DOS bootdisk, creating a file, and
booting to windows results in its disappearance.
-msconfig indicates system is in "selective" startup (with everything
checked), but any change to this (i.e. normal, diagnostic) doesn't do
anything. That is, next boot it's in selective startup again.
b) -BSOD upon startup (crashes before everything is loaded)
-adding 512 MB RAM stops it from crashing on startup, but will crash
after running a Norton scan, an Ad-aware scan, or a Disk cleanup.
Possible that other memory intensive programs reproduce the BLOD. Using
just that new 512 stick and removing old RAM doesn't help....

Actions taken
--------------------
1. Slaved the HD to another one, ran Norton with updated defs, ran
Spybot S&D, ran Ad-aware. No viruses, some spyware. Cleaned system.
Made HD master. Same problems.
2. chkdsk.exe (Dos), Check Disk (Windows), and Norton System Works scan
report 0 hard drive bad sectors.

wrote:

My hard drive is acting strangely.

Doesnt look like its the hard drive.

I've troubleshooted it to two encapsulating ideas:
a) it won't save any kind of change between boots
(yes, i'm admin; no, i'm not in safe mode), and

That wont be due to a hard drive failure.

b) it causes a BLOD under varying conditions, all of which indicate
intensive HD reading or writing (stop code 0x0000008E; only legible
information is "ATAPI.SYS")

Doesnt mean its the hard drive thats the problem.

Details
----------
a) -hooked up a new monitor, every boot it searches
for the driver, finds it, installs it but it's gone next boot

Wont be due to a HD failure.

-created new files on desktop, c drive, or anywhere but they're
gone after reboot. Even booting with DOS bootdisk, creating
a file, and booting to windows results in its disappearance.

Wont be due to a HD failure.

-msconfig indicates system is in "selective" startup (with everything
checked), but any change to this (i.e. normal, diagnostic) doesn't do
anything. That is, next boot it's in selective startup again.

Wont be due to a HD failure.

b) -BSOD upon startup (crashes before everything is loaded)

Wont be due to a HD failure.

-adding 512 MB RAM stops it from crashing on startup, but will crash
after running a Norton scan, an Ad-aware scan, or a Disk cleanup.

Wont be due to a HD failure.

Possible that other memory intensive programs reproduce the BLOD.
Using just that new 512 stick and removing old RAM doesn't help....

Run memtest86+ overnight, bet it shows memory problems.

Actions taken
--------------------
1. Slaved the HD to another one, ran Norton with updated defs, ran
Spybot S&D, ran Ad-aware. No viruses, some spyware. Cleaned system.
Made HD master. Same problems.

2. chkdsk.exe (Dos), Check Disk (Windows), and Norton System Works
scan report 0 hard drive bad sectors.

There is no possibility its a HD failure. You've got some very fundamental
problem with your OS install if you cant write anything to the hard drive
and have it still be there after a reboot. The OS cant be writing anything
to the hard drive for some reason.