Inconsistent but persistent memory errors/BSODs Dell XPS Studio 9100

Have you analyzed the BSOD files, mini dump files with WINDBG or Bluescreenview? please do this.

Also please enable a clean boot in windows and see if this resolved the issue. https://support.microsoft.com/en-us/kb/929135

Please report back with the results.

Failing these also consider running memtest on the computer, this is on XXXXX boot cd you can download this google it.

I have replaced DRAM, hard drive and motherboard  <-- Does replacing the hard drive mean you reinstalled Windows? If just a recovered backup, consider backing up, formatting and reinstalling Windows.

What operating system? Is the computer certified for the operating system you are running?

Disagree we should not just be formatting machines this is a troubleshooting process, just formatting machines is really really bad troubleshooting actually.

Find out whats wrong here. Then make the move on formatting or not. Terrible suggestion.

When all the parts have been replaced and the machine continues to crash, a root kit virus becomes a very likely cause. That is why I suggested reinstalling. In this circumstance it is NOT a terrible suggestion.

How do you know its not a software issue? you havent even suggested reading the dump files!!
there are so many things this could be.

The first step here is to read the dump files, not spend 6 hours rebuilding a machine, this is not the first time you have made these kind of suggestions either and i rarely participate here. Someone with your amount of points should know better, im sorry but that is clear.

What do you think happened when he replaced the hard drive? the OS moved with it?
You should have left this question alone until he responded to my post but we know you.
Just dont even respond to me man seriously, how about if i issue a valid response to a question you just leave it like i do with any question you answer/attempt too.

additionally john my troubleshooting and technical skills are on a different level to yours like this https://www.experts-exchange.com/questions/28789279/Backup-Exec-2015-capacity-edition-TWO-mediaServers.html?anchorAnswerId=41143849#a41143849 and many of the other solutions i post here. I have not been around for a few months but I am back now.

Well since your a site admin ill guess i leave it here, I have no problem with you, I have a problem with you providing terrible solutions over my valid ones like I would any poster.

Cough.

Don't mention hirens cd around here.  It contains illegal software.  A mod will delete any reference to it.

Memtest can be downloaded alone, not just from the mentioned boot cd.

You can get memtest and it is strongly recommended on the UBCD http://www.ultimatebootcd.com/  The UBCD is totally free and legal.

memtest should be the first test to be used.  Two or three passes to see if the memory is up to scratch.  Yes, it has been replaced but that doesn't mean the new stuff is OK.

Possibly a virus.

Try TDSS Killer http://www.bleepingcomputer.com/download/tdsskiller/ first to look at root viruses.
Then AdwCleaner http://www.bleepingcomputer.com/download/adwcleaner/
And then MalwareBytes http://www.bleepingcomputer.com/download/malwarebytes-anti-malware/ (the free version is all you need)
Also look at ComboFix as well if necessary.

Check your temperatures with Speedfan http://www.almico.com/speedfan.php in case the CPU isn't getting proper cooling (that will slow the system down).

Those are your basic tests and note that I'm repeating what has been said earlier by other posters.

>>  Memtest can be downloaded alone, not just from the mentioned boot cd.

Yep.  

Memtest86+ http://www.memtest.org/  (recommended version)
Memtesthttp://www.memtest86.com/

but the UBCD contains that plus a heck of lot more useful utils.

Yep I recommend checking for a virus too.

I like Combofix in safemode from bleeping computer.
Housecall by Trend Micro
ADW cleaner
Prefer Spybot to Malwarebytes now adays.

What about running a clean boot I think that has to be the first step, this could easily be a driver or software issue.

I think the steps are.

1. Clean Boot
2. Dump Files - I would like to see what they say actually, they can just give us the answer in 30 seconds flat
3. Virus scans in safemode with networking.
4. Memtest

That should shed more light on it.

>>  What about running a clean boot I think that has to be the first step, this could easily be a driver or software issue.

This could be anything.

You can add that as another test to do.  But I'd test the memory first before anything else.  Also note that I recommend removing memory chips, giving them a wipe with tissue paper or soft cloth, blowing out memory slots, and reinserting memory chips.  Dust can be a major factor giving memory errors.

Also if there are two memory chips test the system using only one chip.  Two chips can cause errors.

Reason I suggest doing a memtest 4th is because it takes up to 24 hours to run one, all three steps I listed can be completed in 1 - 2 hours. Its also very unlikely to be a memory issue considering all the facts.

I would also add ensuring all drivers are up to date and a full windows update to the steps too.

Wont hurt to go that way.

memtest is a beast of a test anytime I have run it really does annoy me with the amount of time it takes to complete.

I would like the author to comment on memtest because memory was replaced. The replacement could be faulty but usually that is not the case.

Scans as clean with MBAM and TDSSKILLER. Norton is the every day AV and it reports clean, too.

Machine is Win7 Ulitmate.  500GB WD Black.

Some of the BSODS write a dump file, some do not. The ones that do point to a NTOSKRNL.EXE (that's not much of a help)

I will try I BRAND NEW Win7 install. Don't have ultimate in my collection. Professional will have to do.

can you swap the pc to another location?
and put another pc on this location?

and yes - it can be the PS, or AC (eg. not stable)

Virus scanned the heck out of the drive while attached to another system. Found one (generic.fb) trojan. Removed.  

With the drive out, the pre-boot assessment through 2000-0123 when PNY memory sticks installed BUT NOT with Ballistix.

Am ordering Ballistix Tacticals from Crucial. Hopefully all the same ram will eliminate the BSODS. I want to isolate the bad DIMMs.

if they are bad  - not sure yet

glad you have it solved - don't forget to close this Q

This was NOT caught in Dell's PSA or system diagnostics (bother).