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How do you determine how stressed you PSU is????

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Squid

Registered
Joined
Apr 9, 2001
I was wondering how you would go about determining how stressed your power supply is.
I have a fans, DVD, CDW etct etc on a 230W supply, so how do i know when i have too much, will i have a huge crash or..............
Does Win98 detect it or...........

Any ideas????
 

UnseenMenace

UnseenModerator
Joined
Apr 23, 2001
Well it can display in system instability however a good indication is the PSU fan can work exceptionally hard or slow down.. I would also suggest that your PSU is struggling, I would run nothing less than 300w on a system such as yours
 
W

William

Guest
you need at least a 300W, I would recommend getting at least a 350 with what you are running. But I am positive that you need more.
 

oc jason

Senior Member
Joined
Feb 12, 2001
Location
Fayetteville, AR
I think personally that a big PS ia a placebo-i have a tbird 750, 384megs ram-TNT2 16meg, Soundblaster 128 soundcard- 3fans+a GORB fan, a CD ROM, CDRW -keyboard- USB mouse, and a USB Logitech quickcam-on a 200Watt PS and have never had any problems becuase of it. that is a 200watt max so normally its running under 200w
 
OP
S

Squid

Registered
Joined
Apr 9, 2001
OK, but what i was really after was a way of determining how many watts i am currently using, hence determining how much i have left.

I am having no problems at the moment, except the occassional crash of AOE2.

DOes anyone know how to find out what wattage you are using
 

Placid

Senior Member
Joined
Mar 13, 2001
Location
Connecticut
Will show you what psu amd recommends for your cpu.
Another way is to use a program like SiSoft Sandra or other program that will show all of your voltages.
Then put a load on the cpu and all the psu voltages should remain at or above what they should be.
Example if the 12v reads 11.97 then its being overloaded.
 

JaY_III

Senior of BX
Joined
Dec 17, 2000
you could always goto radio shack and pick up a multimeter
that will be able to give you a readout of amps
i got one taht cost me a pretty penny so,, ,i should give it a try
and tell you how it goes,,,,
just check each cable (even ones going to the motherboard) and add
the totals up when you are done.
taht should give you the watts you are using

WATTS DO MATTER
My celeron 2,
192 ram
burner
dvd
2 harddrives
geforce
and the othe crap i got didnt like a 250 watt PSU
the system doesnt stay stable when you are doing lots of stuff, as all
the watts get sucked up....
no i have 2 250 watt PSU's 500watts has fixed all my problems
 

puppet

Registered
Joined
Jun 3, 2001

This is a nice sizing tool......mainly for UPS'... but can sure give you an idea as to how much load you have now.

Choosing a "too large" PS can be troublesome too. Especially if they require a minimum load to operate correctly. If you need to start pulling cards to trouble shoot you might be SOL.

FWIW.......my system uses about 215 watts (306VA) and I've got a fair amount of stuff.
 
OP
S

Squid

Registered
Joined
Apr 9, 2001
Thanks that is more like the information i was after, i will set up my MBM5 and check out all my voltages tonight, and check those links when i get home.
 

Hoot

Inactive Moderator
Joined
Feb 13, 2001
Location
Twin Cities
Plain and Simple.
Do you own a digital multimeter, or can you borrow one? Put the probes into the +5 and return pins of an unused 4-pin molex coming from the PSU in question. If you don't have any unused ones stick the probes into the rear of one going to a drive. Now, run a CPU stressing program like Prime95, Folding at Home, SETI, BurnK6, whatever... If the +5V falls below 4.9, get a bigger PSU. If it does not, leave the stressing program run all night. If it's still running in the morning, keep the PSU. If you rely upon a voltage monitoring program like the one that came with your A7V133, MBM, etc, you will see a greater voltage drop than is occurring at the PSU due to resistance in the ATX cable and plug, not to mention, the traces on the mobo. Personally, with your setup, I would use no less than a quality 300W PSU, but that's my opinion. Don't worry about having too high a capacity PSU.

Hoot
 

Tomas

Member
Joined
Feb 3, 2001
Placid (Jun 06, 2001 05:24 p.m.):
Will show you what psu amd recommends for your cpu.
Another way is to use a program like SiSoft Sandra or other program that will show all of your voltages.
Then put a load on the cpu and all the psu voltages should remain at or above what they should be.
Example if the 12v reads 11.97 then its being overloaded.

Mine is: 12v=11,86v, 5v=4,92, core 3,3v=3,36. core0 1.75v=1.79 and some weird volt i dunno what is: core1=0,11????

So with these voltages my psu is overloaded???? I have a damn 400w psu!! shouldnt that be enough for a [email protected] tbird??? Same results with my old 300w too
 

batboy

Senior Moment
Joined
Jan 12, 2001
Location
Kansas, USA
It's very simple. If you can audibly hear your cooling fans slow down under load and speed back up when the load is removed, then you need a bigger power supply.
 

Placid

Senior Member
Joined
Mar 13, 2001
Location
Connecticut
Tomas (Jun 07, 2001 05:01 a.m.):
Placid (Jun 06, 2001 05:24 p.m.):
Will show you what psu amd recommends for your cpu.
Another way is to use a program like SiSoft Sandra or other program that will show all of your voltages.
Then put a load on the cpu and all the psu voltages should remain at or above what they should be.
Example if the 12v reads 11.97 then its being overloaded.

Mine is: 12v=11,86v, 5v=4,92, core 3,3v=3,36. core0 1.75v=1.79 and some weird volt i dunno what is: core1=0,11????

So with these voltages my psu is overloaded???? I have a damn 400w psu!! shouldnt that be enough for a [email protected] tbird??? Same results with my old 300w too
The difference between a 300w and 400w psu does not mean the max +12v current will be alot more if any.
Your psu is either overloaded on the +12v line wich you can test by unplugging some of the 12v fans or is poorly calibrated. There are 3-300w psu's on this page.
The max +12v ranges from 8a-11a with the 400w giving 12a.
 
OP
S

Squid

Registered
Joined
Apr 9, 2001
I do have a multimeter so i shall give it a go see what the voltage are, i have noticed a drop in fan speed once or twice, so that could be an indication, thats after i just installed the Pioneer 16x DVD and some more Ram,

I think i will start scoping out some PSU's, just sold my old P2 stuff so got some spare cash to play with.

SO some of you guys said do not get a PSU too big, Why??

Bigger the better, the overclockers moto i believed??
 

WyrmMaster

I'm a little teapot Senior
Joined
Dec 17, 2000
Location
Montana, USA
My voltage lines run a little low, even with a 350 watt enermax.

12v = 11.95 to 12.01, varies
5v = 4.91 stable
3.4v=3.36, my IO voltage is up.

I have no stability problems, and im not running much stuff, just the stuff in my sig, 3 90mm fans, a slow hd, a cd drive, and a modem and sound card.
 

Hoot

Inactive Moderator
Joined
Feb 13, 2001
Location
Twin Cities
FWIW, the fans typically speed up during high CPU loading, as the +12 rises in response to the +5V Pulse Width Modulator providing more drive to the transformer to meet the increased current demand.

Hoot
 

Tomas

Member
Joined
Feb 3, 2001
so where do i find an psu that works with an tbird??? The store told me when i bought this thing that it was "MORE" than enough for this tbird. I buyed this because they hadnt any 350s left in stock but still to little power in it??? I havent found any enermax psus in any store in my country yet.......

Also when i used my abit kt7 mobo with this psu i had problems with BIG differences in fan speed/voltage then could really hear the fans spin faster when i loaded it. voltage was 5.09 idle 4.92 loaded. the 12v was always a little low but i think it got higher when i loaded it. On my asus a7v133 i barely hear see any differences in voltage that i thin is because the kt7 used some power saving while idle since i got around 25-27c idle and 45-47c loaded on the kt7 but on the asus the temp is 44-45c idle and 46-47loaded. So its like its running nearly loaded when idling.

Also i had really bad stability problems on the kt7 specially when just when i loaded/unloaded it

Also i have heard it can be the power lines going to ur house that can be the problem?? This 400w should be enough shouldnt it?

system= asus a7v133a, tbird [email protected], 320mb ram

And sorry for the bad english.
 

Hoot

Inactive Moderator
Joined
Feb 13, 2001
Location
Twin Cities
Did anyone read the ninth reply in this thread, that I wrote. I'll repeat the important part for people who didn't/
Under heavy CPU loading, the voltage read on the motherboard can be off by as much as .2V due to voltage drop in the ATX power cable and connector. Do not judge your PSU by the +5V reading on the motherboard. Also, the +12V will go up under heavy current draw on the +5V. That is perfectly normal for PC PSUs. That is why the fans speed up under heavy CPU loads. I have always recommended a 400W PSU if you want to run a Tbird "hot and heavy". They guzzle current, especially at elevated core voltages.

Hoot
 
E

ebola

Guest
when it starts on fire its too stressed. it will happen too, just wait.
 
OP
S

Squid

Registered
Joined
Apr 9, 2001
Ok now a little bit confused, lately i have had alot of crashes through my video card, a TNT2 32meg model 64,
Recently I have added a Pioneer DVD player and another 256 meg ram card.
When i play AoE2 or run 3DMarks at times it crashes and i go back to windows.
So what i tried was disconnecting my Floppy, DVD and CDW then tried the same programs and still got the crashes, hmmmmmm.
Now i have dropped my system back to an A900 and now no problems.
So i guess this point to the need for more power to run my overclocked system, but then why did it not work when i had all the drives disconnected????
And why was it stable before the DVD?????
Any Answers????
Still a bit confused, whether to spend the cash on a new PSU, is it really worth it???