Computer Failure - Unknown Cause

Hey everyone, not sure if this is the write place to post this but we'll see how it goes.

I have recently encountered a series of problems with my computer. To the point now that I am at a bit of a loss as to what to do, besides replacing components 1 by 1 until it works again (which is an expensive option)

First i'll outline my specifications, then i'll go into the problem

CPU: Core2Duo E7500 2.93GHz
RAM: 4x 1gb Kingston HyperX DDR2 800MHz
MOBO: Gigabyte P35-DQ6 rev1.1
HDD: 2x 500GB WD Caviar SATA2 (Mirrored)
2x500GB Seagate Barracuda SATA2 (Was Striped, then Mirrored)
2x 2TBWD Caviar SATA2 (Mirrored)
GFX: Gigabyte HD5870 1GB
PSU: Silverstone 750W
Sound: Audio Kontrol 1 USB.
OS: Windows 7 Ultimate x64

OK, so basically in the last 2 months,
I've had at least 4 hard drives fail, (sometims during RAID and SATA initiation when computer is booting, hard drives come up with FAILED next to them, but then will work after another reboot). In the perfmon, the Disk queue length is always maxed out on the graph, and this seems to coincide with CPU spikes. During these CPU spikes the computer would freeze for up to a minute at the worst of times.
Intel disk management reports hard drive failure almost every time the computer is started up and its scans constantly reveal verification errors.

Also Event Viewer linked the dll file ntdll.dll in relation to programs crashing during these hard drive failure moments.

Just yesterday i put two brand new drives in. after a couple of reboots, 1 failed in the bios checks, and windows 7 install will not install to them (I have them striped)
Also note that in the Intel Raid Management program, pretty much all drives reported failure, and continuously had verification errors (even new drives, even after fresh install and formats)



My graphics card has failed once, catastrophically, and was sent away under warranty for repair. and again when it was returned, and i had it replaced with a new card from the shop i bought it.

My CPU also started getting very hot, causing my computer to crash/shut down without warning. It turned out the thermal paste had begun to burn, and therefor not transfer the heat, (thermal paste only applied 12 months prior.) --- this may not be a symptom relating to my main problem, but still seemed weird.


So i've tried fresh HDDs to see if my old HDDs were broken, problems reoccured.
(New hard drives still have disk queue length that is almost permanently maxed out on the perfmon graph.)

I fixed the cpu with new thermal paste, but it still spikes to 100% at times when it shouldnt, causing media playback to slow down and distort, or halt all together.

I tried a windows 7 repair using the setup disk, which corrupted my os, so cant boot from that drive anymore.

Also note i ran tests on the RAM and they came up all good.

I think that covers everything....
so I am thinking its my PSU, but do PSU's fail this way? where the computer still operates but power is fluctuating in some way?

Or is it the motherboard some how.... i really am not sure at this stage.

would love to hear some thoughts before i burn more HDDs and my GFX card again. at this stage, im leaving the computer off, have pulled it apart and am giving it a good clean.

Thanks in advance, hopefully the answer is out there without having to drop hundreds on new components!

Should also note that this system was built in the middle of 2007

It might be a Power supply problem but, you never know, it could be anything, even the motherboard perhaps. What you can do is check the output voltage of the Power Supply is in between 15% higher-lower range of 5 V, 12 V. If it is not then, you may test another PSU and do the testing again with your machine. One of my friend also had similar issue with his old PSU, it made squeling noises all the time and evetually it just gave in.

Yeah well the psu is not making any noise, but ill get the multi tester out tonight and see if its bad.

update: multi tested the psu, all lines (3.3V, 5V and 12V) register very accurately, also pulled apart the psu cleaned up the dust (which there was A LOT of).
Will run some new tests and see....

Have you tried to do a clean install of Windows 7? One thing I have noticed about the ntdll.dll errors occuring due to the fact is that if you have an Zip drive on the same IDE cable as the hard drive inside your computer. If so, move the Zip drive to a dedicated IDE controller. Also, updating Adobe Flash Player to the lastest version unchecking the option for Enable Third-Party Browser Extensions in some users computer fixed this issue. There are more different issues and different fixes on the same ntdll.dll errors, that you can search and get by searching.

I've tried all the normal things, I've done about 4 clean installs of windows 7 now, and i don't own a zip drive, and all my HDD's are SATA II.


ntdll.dll causing app crashes (already done extensive searches on google, but havent found anything that helped me fix my problem)

SYSTEM process causing CPU spikes that render computer unusable from time to time, found stuff on google that told me to run programs to see what driver is using the SYSTEM process that maybe caused these problems, but cant them to work.

will try adobe thing...

After all the options that was put in front of you it seems that the issue is with the cable there and hence you are getting this issue again and again. It will be nice if you can have a check on the same there. In addition to this also make sure that you see for the cable connection as well. It is the only thing that at the moment I can suggest you here. If possible try to see if you can have something in replacement rather.

Unfortunately i have already tried completely new cables, i think this is solved now, i believe that my motherboard's raid controller has malfunctioned and therefor causing hdd errors, hence the ntdll file (sometimes related to hard drive failure) and possibly the cpu spikes during times of high hdd activity...

still doing more tests to confirm for sure...

Is it an IDE drive? If that is the case then you should verify that the ribbon cable is aligned correctly. You should check that the Red edge for the cable is associated through Pin 1 of the connector on drive. I would like to tell you that Pin 1 is closest to power plug. So check for this and do the changes accordingly and see if that helps you.