Im running a few dev kits for 7 and 8 im going to make some dump files and see if i can find out what Steam is playing with that might be messing up your computer.... i'll keep an eye on this post and report my findings...

Appreciated! You know, this whole thing wouldn't even bother me so much, if it ultimately wouldn't end up dropping the whole PC down, with only choice to reinstall everything.

with out your dumps im not 100% sure but i kept finding errors some small some big with Ntdll.dll its the windows API that programs use to integrate into windows.. steam makes a ton of calls to it at boot up and has a pattern it follows as it calls to this file... its the only commonality i can find without seeing your memory dumps.

I did find a few users on steam forums crashing with this file named as well so maybe that's something.. you can try this from the run command:

"regsvr32.exe /u ntdll.dll"
followed by
"regsvr32.exe ntdll.dll"

Best might be to test with a fresh HDD to see if that will work. If yes, then your old HDD malfunctions or it has malware.

Seeing that Steam is probably spread out over a lot of the disk space, there might be the issue also if the HDD is bad.

Getting "The module "ntdll.dll" was loaded but the entry-point DLLUnregisterServer was not found. Make sure that "ntdll.dll" is a valid DLL or OCX file and then try again."

Don't really have fresh HDDs laying around!

Don't know why, but it seemed to have stopped. I didn't change anything, didn't install anything new or uninstall anything old, didn't fix anything, so not sure why... but it stopped.

Quick question. Do you have any issues with screen freezes, where the pc becomes unresponsive for a short period of time? Do you play any graphic intensive games and graphics not load up sometimes?

Fair enough. I only asked because I have just had to replace my hard drive due to massive failure. It started with webpages and such freezing on me, games not loading graphics properly and constant crashes, then BSOD constantly. So asked just in case it was a similar issue.

On a side note, have you thought about formatting your hard drive (if you have files you don't mind losing) and reinstalling windows to see if that helps any? I know it is extreme, but I get impatient when things go wrong, so to save time I just format and reinstall :P

My issue was a pain because I only had the one hard drive, and it was partitioned so it had 1 for windows and system files, and one for everything else. Do you have one hard drive for windows and one for everything else or is it partitioned like mine was?

memtest+, always run this first. But yeah, this, in general is about as good as you're going to get.

You can check the model number and firmware version for your hard drive and other stuff that's similar, sometimes they have known flaws fixed in later versions. Don't update this shit just to update it, though, it's not the same thing as a security patch.

Yep, all I have is on one drive and I have tried reinstalling windows before and it did help for a month or so. But anyway, I still have no idea why, but the problem seems to have just disappeared, just when I wasn't even trying anything to fix it anymore.