BSOD 7a and f4 on clean windows install

Hi. Since yesterday my PC is giving me BSOD`s (Mostly on startup/logon, but some of them are random too.)

The error codes seem to be 7a and f4.

All the files you ask for in the how-to thread are attached.

About my PC:
Win7 x64
Ram: 12GB Corsair Vengeance triple kit.
HDD: Western Digital VelociRaptor 600gb
CPU: i7 950 @4*3.06
GPU: Sapphire Toxic HD5850 2GB
MB: Sapphire Pure Black x58
Case and CPU are well cooled.

Thank you,



Noob Whisperer
You seem to be getting all;
A process or thread crucial to system operation has unexpectedly exited or been
Several processes and threads are necessary for the operation of the
system; when they are terminated (for any reason), the system can no
longer function.
And two suggest,
Probably caused by : hardware_disk
You should probably consider running
chkdsk C: /R
from an elevated command prompt
and perhaps even consider obtain a vendor specific hard drive diagnostic utility from your drive manufacturer just to be safe.
while the other two suggest
Probably caused by : csrss.exe
And again just to be safe download and run this How to remove malware belonging to the family Rootkit.Win32.TDSS (aka Tidserv, TDSServ, Alureon)? and follow that up with MalwareBytes download, install, update signatures and reboot into Safe Mode and run a full system scan. Malwarebytes : Malwarebytes Anti-Malware PRO removes malware including viruses, spyware, worms and trojans, plus it protects your computer
And just to be extra safe grab a blank CD and download this program from here Microsoft Standalone System Sweeper Beta | Microsoft Connect double click it and it will build a bootable CD with which you can boot your system and perform a full, offline scan for problems resulting from malware or virus infections.
Your memory is a bit out of whack at 8, 8, 8, 20 and 1T where I would expect 9, 9, 9, 24 and a command rate of 2T so you can either use your system BIOS to set that correctly manually or you might try enabling XMP (Extreme Memory Profile) from within you BIOS and see if that helps.
Additionally update this old driver
yk62x64.sys 2/23/2009 Marvell Yukon 88E8057-PCI-E-Gigabit-Ethernet-Controller either from here Sapphire Technology Web Site or even better from here Marvell - Support - Driver Downloads
Good luck and keep us posted.

Ok, I have done most of those things before, but -just to be safe- I have done everything again.
1) chkdsk and WD's diagnostic tool came back without any error (I changed the SATA cable, the 7a bluescreen did not occur again afterwards.)
2)All the virus scans came back clean (well, the 1st one told me my VCD driver is suspicious...). I could not run the microsoft sweeper though, but more on that issue in a minute.
3) I have enabled XMP. (In case it matters: My windows seems to detect 8 out of 12GB RAM)
4) I have updated the driver.

About the new issues...
After changing my SATA cable everything was running fine for some time until today. BUT: Today when I first turned on my PC everything locked up (at first firefox and then, when i tried to close it, the explorer locked up too. I was unable to open the task manager and ctrl-alt-del did not work either. After two restarts (everytime because of the same issue) the pc seemed to work, so i started a game. Shortly after that my PC crashed yet again, giving me a f4 bluescreen. I can only boot in safe mode now as it still freezes everytime I boot up normally, so I can't use the Microsoft sweeper tool atm. After sending this post I will try a system restore point. Wish me luck.

btw: sorry if this post is a little messy/confusing. I didn't sleep too well and i tend to write pretty strange stuff :p

Anyways thanks for your support, I hope we will get this PC fixed soon.


Noob Whisperer
The Microsoft Standalone Syetem Sweeper does not rely on an operating system. It boots from the CD and then you choose Full System Scan. So you should be able to run that regardless of whether or not you system will boot into the OS.
Download Memtest86+ from this location here. Burn the ISO to a CD and boot the computer from the CD from a cold boot after leaving it off for an hour or more.
Ideally let it run for at least 7 passes / 6-8 hours. If errors appear before that you can stop that particular test. Any time Memtest86+ reports errors, it can be either bad RAM or a bad Mobo slot. Perform the test on RAM sticks individually as well as all possible combinations. When you find a good one then test it in all slots. Post back with the results.
See this Guide to using Memtest 86+

The Sweeper might be able to run without os, but it won`t create the cd...
I have, however, now managed to prepare the CD and will run the Sweep tomorrow. Then I will probably run the mem test and report back here on saturday. Until then,

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