Advice needed on my PSU readings

[Mithrandir]

Hi,

Hope I can gain a better idea of my PSU voltage readings.
I understand the importance of having stable power, but would appreciate help on interpreting what the following shows.

Many thanks!

[0iD]

The more the rh readings resemble the lh ones the better prettymuch. Those look fine to me really. Is that under load or idle? For a real test, put the psu under a bit of stress.

[muddyfox470]

What is you System Spec?

What model is your PSU? and if possible can you give out the rail (ampage) values on each of the rails for your PSU. i.e. +3.3v, +5v and +12v

Then we can see why the readings are as they are

Ian

[Mithrandir]

Thanks.

Well the PSU came with the case when I got the system over 5 years ago from Mesh. (model no on label is ATX-1125B

It's a 250w and has the following

+3.3V------14A
+5V--------26A
+12V-------9A
-5V--------0.5A
-12V-------0.8A
+5sb-------1A

+5V & +3.3V Total Output 130W

My PC specs are:
AMD Athlon 900Mhz (2x coolermaster fans on heatsink)
Gigabyte 71XE
768MB ram (3 x 256mb)
Inno3D Geforce 4 ti500 (AGP)
Audigy soundcard (PCI)
Firewire/USB 2 card (PCI)
Pace TV card (PCI)
Network card (PCI)
Modem (PCI)
Akasa system cooler fan (connected to internal power)
DVD drive
DVD-RW drive
6 in 1 card reader/usb/firewire front bay
Floppy drive
2 x Hard drives

This is all I could think of connected to the power source.


Regards

[peterb]

The actual output voltages under max load should ideally be within 5% of the rated voltage.

[muddyfox470]

Despite that PSU not being up to todays standards - i.e. it wouldnt be able to power many of the really expensive systems around here.

It should do admirably in that system of yours (and if it has lasted that long it means it is doing well).

The original rails you showed (the pic) are pretty good, so long as they are pretty much stable and dont fluctuate too much they seem absolutely fine, you shouldnt have too much trouble with it! (as peterb said +/- 5%)

Just watch it if you start adding more drives etc, or a newer graphics card.

Thanks for all the info, and well it doesn't look like much needs changing. If the PSU is cooled by a fan, and it does start making strange noises, it could be that the fan is about to die! But from those readings it seems the PSU is coping well and could reflect well on the PSU or the low power consumption of the components!

Was there anything else you wanted out of this?

Cheers

Ian

EDIT: The -5v and -12v have very little relevance, tbh i dont actually know exactly what they do, all i know is that the new P4 standard doesnt require the -5v no more!

[Mithrandir]

Thanks for the info guys.. I snapped the reading after a reboot and the PC was not running any programs. Howcan I test the PSU under a 'load'? I've always thought the amount of things connected was stressing the power as I do get freezes from time to time.

[peterb]

Run MS Word! That uses a lot of CPU resources (regularly causes the fan to fire up on my laptop) Linux also tends to stress a system, try running Knoppix off a CD ROM.

[Sk!mD4Rk]

Get Prime95 here http://www.mersenne.org/freesoft.htm to stress your system
and http://www.daionet.gr.jp/~masa/rthdribl/ to stress you GFX card

Run them at the same time as well!

[peterb]

Of course, if you REALLY want to get paranoid abot your PSU, you could put a 'scope on the outputs and check for spike, noise etc, and then you can start looking at regulation under transient loads etc, recover times, feedback loop time constants etc... Then examine how transient load changes on one output affect the regulation on other outputs etc. A whole world of fun and investigation awaits you!!

[Mithrandir]

Thanks for the feedback guys, but I've decided to get a new PSU as I need to start upgrading my PC anyway. I've gone for an Enermax EG465AX-VE.
That should be plenty of power I think for now!

Next will be a case so I'm gonna start a new thread elsewhere to get some additional feedback.

Cheers!