PC Restarting - Mainly when gaming

Gimpymoo · 29 Jun 2009 at 21:31

I think my PSU maybe the culprit.

AMD 720BE 2.8Ghz Tri-Core
AMD 4850 512MB
6 x HDD'S

OEM PSU = 400W

Now, is that uber under spec?

Never had that problem before, been running the rig since feb.

I am only using the stock CPU fan with limited case cooling.

CPU at 60 degrees under load, this shouldn't force a restart should it?

So, what you think, CPU fan or have I beat my 12v rail into submission - lol

SKaRT · 29 Jun 2009 at 21:44

Almost certainly PSU, the CPU wouldn't restart at 60. Would get much higher before it auto shutdown for heat.

BENdage · 29 Jun 2009 at 21:53

I agree its most liely the psu. Have you had a look to see how your rails are when under load? You can use speedfan to graph the 12v rail while gaming and have a look when you finish to see if its dropped. If it has its a sure sign of an overloaded PSU.

Ghost-Reaper · 29 Jun 2009 at 22:17

that is most likely a bad quality psu that is not providing anywhere near its stated wattage, and considering it happening when you are gaming over time the psu must have degraded.

Gimpymoo · 29 Jun 2009 at 22:26

BENdage said:
I agree its most liely the psu. Have you had a look to see how your rails are when under load? You can use speedfan to graph the 12v rail while gaming and have a look when you finish to see if its dropped. If it has its a sure sign of an overloaded PSU.

Good idea.

Will run it on the second screen while gaming and see what happens, thanks.

baten · 29 Jun 2009 at 22:26

i always work out the PSU wattage to use like this, work out watts needed by machine+ roundup to nearest 100 add 25%, and make sure the the rails can supply enough current.

FYI watts = volts*amps, amps=watts/volts volts=watts/amps

i have found the closer to their load max you run a psu the more un stable it is and quicker it fails, and by look at reviews, even some top brand PSus blow up at high loads.

hope it helps someone

Gimpymoo · 30 Jun 2009 at 09:45

Gimpymoo said:
Good idea.

Will run it on the second screen while gaming and see what happens, thanks.

OK, Speedfan logs the lowest value to be 11.52v. Obviously, I assume it is unable to log the exact voltage at the moment is restarts.

It averages between 11.65v - 11.71v.

Is 11.52v considered low?

Dammiz · 30 Jun 2009 at 11:58

AFAIK the voltages have to be within 10% of the supposed value so the 12V line must be withing 10.8V and 13.2V but still this is only the bare minimum to be able to let the pc work properly... then again 11.52v is still VERY low imo... what Amperage is the 12V rail supposed to be capable of carrying? if it's old most probabbly the 12v line is dying/ under specced...

Edited the math ^.^ sry

95thrifles · 30 Jun 2009 at 12:07

your maths isnt very good, thats 1% not 10% what youve quoted, however the accepted tolerance for what is considered good is less than 3%, almost always less than 12 not above, so 11.64 and up is good

TheBlackShuck15 · 30 Jun 2009 at 12:20

If you have a spare power supply lying around then you could try a different power supply in the computer. But try to make sure that the different power supply is at least the same if not more powerfull than your current power supply, idealy you would go for a named power supply at about 500w or more. If you are still getting the same problem try replacing other components untill you dont get the problem any more.

Dammiz · 30 Jun 2009 at 12:28

95thrifles said:
your maths isnt very good, thats 1% not 10% what youve quoted

oops sry

must be still asleep this morning

haha anyways sry for the math

BTW I checked out what desired tolerences should be for a psu and this is what I found:

Desired Voltage,Loose Tolerance Min (-10%), Max (+8%), Tight Tolerance Min (-5%), Max (+5%)

(+3.3V 2.97V 3.63V 3.135 3.465)
(+/-5.0V 4.5V 5.4V 4.75 5.25)
(+/-12.0V 10.8V 12.9V 11.4 12.6)

OpenToSuggestions · 30 Jun 2009 at 12:31

Get a new psu.

A cpu at 60 degrees is normal.

alex24 · 30 Jun 2009 at 12:35

I've never had much luck monitoring voltages for fluctuations on crashing PSUs as I've found they drop out suddenly sometimes and it's just not logged before it reboots or freezes up. Definitely sounds like your culprit, even if it's not i'd never use a cheapy one with any half decent components I cared about.

Gimpymoo · 30 Jun 2009 at 12:43

http://www.overclockers.co.uk/showproduct.php?prodid=CA-032-OC

Would that be a good buy?

alex24 · 30 Jun 2009 at 12:47

Yeah, that's a pretty good PSU at a very decent price, though might be overkill for the system you've listed up there.

Gimpymoo · 30 Jun 2009 at 12:51

I quiet fancy a modular PSU though and these seem the best Value/Performing ones I can find although is my thinking flawed and a none modular one is just as good?

At the moment, the 700w is only £4 more than the 600w although it is £15 MORE than the 500w although I feel the 500w would not give much headroom for future upgrades.

TheBlackShuck15 · 30 Jun 2009 at 12:55

You could also consider this.

alex24 · 30 Jun 2009 at 12:59

I would go for a modular PSU every time now, makes cable management and airflow much better. Most decent PSUs are modular now anyway.

Seasonic make probably some of the best supplies out there, but expect to pay a premium. From what I understand, Corsair supplies are based on seasonic designs, and are very good quality. The HX series is modular and a 520W should be enough for you. My PC in sig is running a HX620 and is very happy with plenty of power should I upgrade.

TheBlackShuck15 · 30 Jun 2009 at 13:02

Yer thinking about it you are probably better off with a modular psu (I diddnt see that the OCZ was modular the first time round).

Gimpymoo · 30 Jun 2009 at 13:03

Mmmm... Appears to have slightly better build quality/Components than the OCZ one...

Conflicting reviews though:

Reviewed by: Ben Taylor

The cables are as have been said, quite long so fitting un used cables in a 'smaller' case can crowd the components slightly.

Reviewed by: Russ
No bells and whistles on this PSU but it does its job and quietly. Note although the cables are long I found fitting in a large case (Antec 1200) to be problematic as a few of the cables only just reached.

LOL

The Seasonics look nice but would prefer a little more juice than 500w, if only for Future VGA/CPU upgrade.