Hi
First post here, and i'm afraid it's a bit of a doozy of a problem, so any help would be greatly appreciated.
I got the parts for a new system the other day and have been having problems with it randomly freezing after I tried to add the second 2gb memory module (I had heard Vista 64 had problems with more than 3gb of ram unless it was patched/sp1, so used one module for the install).
The spec is
Intel q6600
Asus P5k Premium wifi revision A03, Bios 0404
Crucial DDR2 800 2gb modules
Seagate 500gb HDD
Antec Sonata 550 with 550watt PSU
Normal anti-static precautions were taken (wrist strap worn at all times, pets and small children kicked out etc)
Basically the build went like a dream, and was running happily until I powered down (and turned off at the mains) and went to fit the second Crucial memory module.
After fitting the second module Windows kept crashing, so I ran the vista memory test (on the DVD) which reported a problem.
It's also now crashing in the bios/at boot - if it's crashed it needs a full powerdown (and power off at the mains/supply), or it tends to lock up during the bios boot screen.
Removing the second module seemed to clear the problem up initially, but when I booted the next morning I was seeing the same problems I had when the second one was installed.
It's even crashing during the bios/before it hands over to the OS.
I've tried the following
Reseating the memory - i've tried the first module in all the slots on it's own, and in slot A1 with the second module in A2.
I've tried the second module in Slots A1, A2 (with module 1), and B1.
I've tried raising the DRAM voltage from the recommended 1.8 to 1.85 and 1.9v
I've tried the video card in another machine - one of the symptoms when Windows crashes is the screen goes funny, so I tried it in a friends machine for an hour (the longest mine is staying up since the problem started is about a minute or so), to try and rule out overheating/faulty card.
I've tried the machine without the optical drive, so it's just booting into windows
I've tried it with just the optical drive so it's booting to the vista install disk (and the memory test on it).
I've tried it with a USB memory stick - the plan was to try and flash the bios, but gave up on that idea
It hardlocks with all 3 of the above after about a minute.
I've tried disabling all the onboard features that are optional (networking, audio, firewire, third party ide chip
I've tried the basic system outside of the case on the motheboard box to rule out shorting (i used some spare motherboard risers I had).
Despite all of those tests at the moment the system will only remain operational for about a minute or two after booting from cold, and then seems to lock up completely (ignores keyboard commands), and a forced reboot tends to result in it locking up again during the bios screen.
It's even crashing when sat in the bios - despite the CPU temp not going higher than about 55c according to the hardware monitor.
It's starting to look very much like i've either got a pair of duff memory modules (or they are not compatible - they were bought using the crucial memory tool on their website), or something has died/is overheating on the motherboard.
I'm about at a loss as i've done virtually all the checks I can think of/can do with what i've got available (I don't have spare DDR2 memory, and the only PCI Express motherboard i've got access to is an AMD).
I'm waiting on a reply from Scan tech support at the moment as that is where I bought the motherboard/cpu/videocard, but if anyone can think of any other tests I can try the help would be greatly appreciated.
Thanks in advance