PC shuts down without notice

[anarchon]

Hello all !

So I have a hardware problem with my newly aquired machine..
It just shuts down without notice, ..
At the beginning I thought it might be due to AC power loss or a bad PSU,
I checked in my bios the reboot on Power loss option, but my computer just ignores this setting and remains powered off.

Another odd thing is : when it shuts down my adapter for my wireless mouse and keyboard remains powered. (is not the case when I shut it down normally)

If I run a game like call of duty 2 in highest Graphical mode I can be sure it will be shutdown within 5 to 10 minutes.
It also happend 1 time when I left my pc running for +/- 24 hours.

These are my specs :

Antec NeoHE 500 High Efficiency 500W PSU
A8N-SLI Premium S939 nForce4 PCI-E DDR ATX
AMD Athlon64 3800+ X2 Dual Core S939 Boxed
SoundBlaster X-Fi Elite PCI 24bit Retail NL
MSI nVidia GeForce NX6800GS-TD256E PCI-E 256Mb TV Out & DVI
Lite On SHW-16H5S DVD±RW 16x LightScribe bulk black
Lite On SOHD-16P9S DVD 16/48 bulk black
Zalman CNPS9500 LED
WD Caviar 2500JS : 250 Gb S-ATA II (7200/300-8Mb)
Corsair Twinx 2048MB PC3200 CAS2

So I already used memtest86+ with 1 pass.. I imagine that if there is a problem with the Ram or processor (or Bus in between) the problem should have occured during this test.

I also calculated the approximate amount of Watt I need but I think that i'm quite safe with a 500 W PSU

My next step is to launch 3Dmark2006 and see if it might be a problem with my graphical card..
which i'll do as soon as my download has completed.


Is there any other troubleshooting step I might be able to do?

thanks for helping me out guys.

 

[jeremy]

when it comes to psus its not the wattage one should be looking at , its mainly the amper rating , various psus of same *wattage* have diffrent amper ratings , the antec neohe series simply suck its largely underpowerd on the ampers, that neohe 500w have only 23A on the +3.3v and 17A on the +5v i doubt thats enough for your system , its gotta be the psu or the processor overheating but i bet on the psu , download asus pcprobe2 (click *utilities*)
http://support.asus.com/download/download.aspx?SLanguage=en-us&model=A8N-SLI Premium
take a screenshot then ill know for sure

 

[anarchon]

I already checked the heating .. and it's cooled at 29 - 31 C°
so you are right.
Ok I'm going to download it !

 

[anarchon]

Ok I attached the screenshot.
What do you think ?

 

[jeremy]

defintly the psu those +12v/+5v are way too low , i suggest youll get one of these

antec truepower2 550w eps12v (the truepower series is much better on the amps)
http://www.newegg.com/Product/Product.asp?Item=N82E16817103932
ocz powerstream 520w
http://www.newegg.com/Product/Product.asp?Item=N82E16817711002
both arent modular , but its not easy to find a quality modular psu (with good amps that is) , and incase youll ask yourself "wheres that 4pin plug?" its in the 8pin one (4+4 detachable)

 

[anarchon]

okay i'll folllow your advise.
I noticed lot's of fluctuations on the V-core while playing a game.
anyway I was browsing some other forums and found a person with the same cpu.. he had this :
CPU Core 1.42 V
+3.3 V 3.31 V
+5 V 5.13 V
+12 V 12.10 V
+5 V Standby 5.09 V

it's clear that I have a Voltage problem :-(

Well I'll fix it asap and let you know if it fixed it.

Jeremy, thanks a lot for your help and if I can help you with more network relates items, let me know.

 

[Nitestick]

look up how to measure the voltages with a multimeter if you think you would be able to do so. its far more accurate than the motherboard sensors.

 

[jeremy]

not entirly true , years ago there were some mobos with very inaccurate sensors , but in *modern* mobos the sensors are accurate nearly as a multimeter , anyway can you honestly say a psu with with amp rating of +3.3V@23A , +5V@17A , +12V1@17A, +12V2@17A can handle those specs above? obviously not

 

[Nitestick]

the psu should work in my opinion. motherboard sensors are often innaccurate but are generally precise. in other words the readings are correct but the scale is wrong e.g. say 12v reads as 11v and 11v reads as 10v, the reading is still precise but is not accurate.

 

[jeremy]

well my take on it aint really based on opinion its based on power consumption of the specs above +3.3V@23A , +5V@17A cant possibly be good enough for those parts, and just to prove my point have a look at newegg reviews youll see that several ppl with similar specs had the same issue with that psu , anyway i didnt say mobo sensors are 100% accurate i just said their more accurate then what they were before and that while a multimeter is indid more accurate its not by much with modern sensors , few months back i stress tested with prime95 and monitored with everest & multimeter at the same time and the truth is the multimeter was just a tinybit more accurate