-12V tolerance on PSU
 

I'm having a problem with my PC locking up maybe two or three times every couple of days - even when left idling whilst running my weather station software only. I see from running CPUID that my -12V voltage is -14.78V which Google tells me is outside the ATX 2.2 tolerance of -13.2V. I don't have the skills or nerve to muck about with testing electrickery items so:

Question - could my PSU be causing my problem? I've cleaned out any dust throughout and CPUID shows my temperatures are all okay.

http://i1123.photobucket.com/albums/...eSix/cpuid.jpg

Is the -12V used for anything nowadays? I thought it was only for the serial interface. (RS232)

Edited to add I don't appear to have -12V on my mother board.

Depends on the load on the other rails and how good the psu is. Not all the rails are directly regulated, but depend on the load on, say, the 5v or 3.3 volt for a reference. If either of these are heavily loaded, the psu outputs more energy to keep the voltage constant on these two rails, while the others will rise. Good quality psu's make a better job of regulating the various rails, but there's always a tolerance. The -12v may not even be used, other than for things like serial ports, which many machines don't have now.

As for the fault, give the machine a good dust out, remove and reseat cpu, memory and any accessory cards in the slots, power connectors to the motherboard and drives. If you don't have an anti static strap, ground hand to machine case *before* removing components. If this doesn't fix it, most likely a hardware fault on the motherboard or one of the accessory cards...

Regards,

Chris

looking at the spec of that board, two things come to mind
ASUS - Motherboards- ASUS M2N32-SLI Premium Vista Edition

If you're running Win7 it may well need a BIOS update to work properly

Secondly, i see it has six nVidiia SATA ports (capable or RAID) and a single internal Silicon Image SATA port as well. Which are you using for the drives? If the SiL one I'd switch to the nVidia ones
Also is the RAID software running? if it is, but a RAIS is not actually configured that could cause similar symptoms

But -and heres the but - its an ASUS board, and an nVidia chipset. I wouldn't expect either to last more than around three years

However - usual checks
Reseat eerything, clean all the dirt and dust out. Are the fans ckean and running freely (especially the graphics card). Check the memory for faults, download and run the relevant diagnostics for the hard drive

Just coming back to what I said before, unless you have a newer variant of that board, theres nothing on the support site to suggest it will support Win7.
Last BIOS update was July 2009, and Win7 is not listed as a supported OS


You've not said which OS you're running, but it may be part of the problem

Windows 7 Compatibility for M2N32-SLI Premium: Drivers, Updates, Downloads

MS seems to suggest that the board runs just fine with Win 7.

SD

Many thanks for all the comments. The computer is a home build and the board is about 5 years old and after using Vista has been running Windows 7 Home Premium 64-bit since just after it was launched with no problems until recently. I did check at the time that the board was compatible with Windows 7 and I think I flashed the BIOS at the change to 7 - can't remember for sure.

PSU is an Antec TruePower, 850w if I recall correctly. The drives are using the nVidia ports - not using RAID. The one with the OS on it is is the same age as the board - 5 years but all safely backed up. Sometimes when the computer freezes the hard disk light stays permanently on, sometimes it is off.

I've turned off my weather station software as I'm deeply suspicious of it being the problem and will see if I get any freezing for the coming week. It's been running on an old XP laptop for the last 4 years - quite often with different problems to the current one - and was only transferred to this computer three months ago. If the freezes still occur during the coming week then I'll set about reseating everything and running memory and drive diagnostics.

Another thing you can try to get some idea if this is the machine going off into the deep, or a hardware fault, is to bring up the task manager before the freeze and set up for "always on top" mode. If the fault is software related, the t/m will show which task is consuming all the resources and also the state of memory, swap space etc. The clue may also be in the h/d activity light, which may be thrashig due to not enough memory, or even a disk fault, giving the impression of a lockup. What happens if you just leave it for a few tens of minutes?. Does the h/d light eventually go out, for example. If you put your ear near the drive, does it sound active, ticking noise, whatever ?.

Do try reseating all the hardware connectors and parts though, as suggested in my previous post. Ime, this is the most common cause of unrecoverable lockup where the software hasn't itself crashed....

Regards,

Chris

Some "weather station" software is actually spyware / rogueware and comes bundled with the Conduit engine (among other bits of crapware)

It would be worth giving the machine a runover with Spybot and Malwarebytes

Quite happy that my weather station software is legit - it's Weather Display, is well supported by its author Brian Hamilton and has over 3500 of us using it worldwide with excellent forum activity and advice. However it is advised to "Run as Administrator" on Windows 7 as it was an XP program when first released. Spybot and Malwarebytes don't show any problems.

Re the HD light - if it's on during the freeze then it stays on permanently until I press the reset. No ticking noises apparent and I have 6gig of memory. Good idea about Task Manager - running "on top" now.

try a new IDE / SATA cable for the hard drive
If its SATA also try it on another SATA header on the motherboard
What make / model of hard drive is it?

The OS Drive is a Western Digital SATA 400Gb WD4000AAKS Caviar SE16 (bought June 2007), split into two partitions, one for the OS and one for programs. The other two drives are also Western Digital, used for data and photos/video etc.

I'll dig out a new SATA cable later today and keep it ready to try it on another header. I want to run the computer "as is" with the weather software shut down for a few days to see if the freezing still happens. If it does then I'll start reseating things and then change bits one by one. Thanks for all the suggestions so far.:ok:

download the Data Lifeguard diagnostics for DOS from this page
WD Support / Downloads / SATA & SAS / WD Blue / SE / SE16 (SATA II)

Use it to create a CD ISO, burn it then boot the machine with it and test the drive

Problem solved I hope. For some reason my Silicon Labs CP210x USB to UART Bridge driver has rolled back to version 5.3 whereas the current version is 6.5.3. This driver is necessary for communication between my USB Davis VP2 weather data logger and my PC. Seems I am not the only one to have locking up problems with these earlier drivers. No idea why it has rolled back on its own - I wasn't on the most up to date driver but 5.3 was superceded ages ago.

Many thanks again for all the suggestions.

Thats an obscure one

I seem to remember problems with their gear in the past though.....weren't they the ones who sold clones of the Psion 5 organiser? I had one and had problems with it

back to to the topic - I'd guess that a Windows update put in an older signed generic driver in place of the correct newer one
Check the Microsoft Update records - and be more selective over which of the "optional" ones you seelct
However I'll repeat - thats a guess