[mdq]

Hi, new tothe forum here, and hardware side of pC´s too, so please bare with me a little.

Here are the specs for my PC:

-Intel Core 2 Duo 4300 1.80 Hgz

-2GB Ram, 2 modules, OCZ DDR2 PC2-4200

-MSI mother P965 Neo-F V2

-Videocard Nvidia GeForce 8500 GT

-Power supply Vitsuba 400W

-Western digital hard drive WD1600AAJS


ISSUE: I´ve had this PC running without problems for almost a year and a half now. Abouth a month ago, it started shutting down randomly without warnings, error logs, blue screens or anything at all.

This happened mostly on heavy load, but could also happen when PC wasn´t doing anything at all.


SOLUTION ATTEMPS: After coming across many forums, I tried the usual. Swapping power supply, swapping Ram modules and switching slots, formating, etc.

After many tries, I´ve been able to stabilize the machine by disabling Core- Multiprocessing function from BIOS settings. Now, CPU doesn´t go over 40 degrees but I have one Core disabled, wich sucks big time but doesn´t shut down.


CONCLUSSIONS: So far, I´ve been able to narrow the problem to this:

Shutdown happens almost everytime on heavy load. Running Prime 95, was able to replicate the problem everytime. It shuts down at the same time that CPU reaches near 50 degrees temperatures.

Here´s a screenshot with results from Speedfan. Everest shows the same values. I´m particularly concerned about the 70 degrees in temp 3, wich seems to belong to mobo temp according to everest. These were ran with one core multiprocessing disabled

http://img29.imageshack.us/img29/7349/speedfanonecore.jpg


I must add that after every shutdown, Pc starts inmediately by itself, without pressing buttongs andwithout error supports.


SOLUTIONS: Right now, I don´t have another CPU or mother to swap for. The alternative could be better cooling, but I wouldn´t know where to start being a newby on this subject.


Any help would be really appreciated since I work with this computer

 

[HD_Monkey]

Not to get too technical. Electrical resistance increases with temperature increase and that is really what these sensors measure. Temp 3 is an open circuit and therefore is mistakenly showing 100% resistance as a high temperature. You can ignore it. Mine acually shows temp 3 as over 100c. 50C on a stress test is well within specs. You said you tried a different power supply. Are you sure it was of good quality?

 

[mdq]

Well, it was a brand new Eurocase power supply, so I guess it was fine.

However, the only change that kept it from shutting down was as I said, disabling the Core multiprocessing in the Bios.

That way, if I run Prime 95, there´s not shut down and CPU stays at 40 degrees. With multiprocessing enabled, temp rises up to 50 degrees and shuts down.

 

[HD_Monkey]

There a lot of power supply manufacturers. Brand new means nothing. I meant what are the specs. model, wattage. Never heard of eurocase or vitsuba. Looked up vitsuba, but don't speak spanish. If you are running one core then you are using less power. A bad power supply will cause your machine to shut down during stress test. A core 2 duo at 50C IS NOT HOT!!!

 

[Tyree]

Sounds like a power problem. Can you get or borrow a quality PSU to try?
http://www.techsupportforum.com/f210/power-supply-information-and-selection-192217.html

 

[mdq]

Well, the Vitsuba power supply I´m using is 400 W 230/ 115 VAC 10/6 A 50-60HZ.

The other one I tried, Eurocase was 450 W. Since it has more wattage I thought in my infinite ignorance that I could discard the power supply as an issue.

Specially because I´ve been using my PC with a 400 W power supply for a year and a half and that seemed to be enough.

 

[HD_Monkey]

You could have a cheap psu rated at 600W that is only really giving you 300W so it makes a huge difference who built it.

I recommend taking a look at the following:

http://www.techsupportforum.com/f210/power-supply-information-and-selection-192217.html

There are several known reliable psu manufacturers and models toward the bottom of the sticky.

 

[Tumbleweed36]

The rig might have run O.K. for a long time, but power supplies as the capacitors age, begin to put out less power, then they get warmer, which also creates less power....you get the picture, they begin to not be able to pull the load. Try a decent power supply in there if you can and my guess is that would solve your issue. The following are considered good brand names:

Seasonic – Any Model
Corsair – Any Model
PC Power & Cooling – Any Model
Thermaltake – “Toughpower” Series Only
Coolermaster – “Real Power Pro” Series Only

 

[mdq]

Someone told me in another forum that the replacement power supply I used was even worse that the one I have.

Is there any way/ software to test if my power supply is working properly?

I just want to be as sure as possible before buying spare parts randomly.

 

[dai]

you need to be up here

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139004&Tpk=corsair+550w

a 400w will not have enough amps on the 12v line