Is My PSU Dying?

[Format _C:]

The Voltages Seem Low even at idle
+3.3 +5 V +12V -12V -5V
3.11 + 4.67 +12.16 -12.16 -5.06

Its an Older antec SL350 that came with a case like 3 years ago so is it past its prime or am I overloading it?

System Specs
Asus A7N8X Deluxe Rev 2
CPU AMD Athlon XP 2600+ Retail
512MB Ram 256MB x2 Micron
Maxtor 6Y160P0 DiamondMax Plus 9 7200RPM 160GB ATA133
Mitsumi 1.44MB 3.5"
CD-ROM/DVD-ROM Pioneer DVD-106S/2 16X DVD/40X CD
CD-R/RW LITEON SOHR-5238S 52X Write X 32X Rewrite X 52 X Read
DVD Burner NEC ND-2500A Attached to a Maxter/Promise Ultra133 TX2 IDE ATA133 PCI Card
NIC Buit In To Motherboard Using Nvidia Nic
ATI Radeon 9600XT 128MB DDR AGP 8X Graphics Card
Logitech Z-560
Keyboard Logitech Elite Keyboard
Mouse Logitech MX510 Blue
Case ANTEC Performance Plus Metallic Gray PlusView1000AMG With 350 Watt Antec Power Supply
OS Microsoft Windows XP Professional SP2

and if I get a new PSU what one should I get? 24 Pin? So I can upgrade to a 24 pin MB when prices drop?

 

[larrymoencurly]

I'd measure with a digital multimeter because I'm not sure that a mobo can even boot with the +5.0V rail down by 6.6% and the +3.3V down by 5.8%. OTOH I have a 300W Antec about the same age that developed some bad capacitors on its rails last year, probably because they were part of the Taiwan capacitor electrolyte scandal, and bad caps can voltages drop.

 

[Format _C:]

Digital Meter says
5V 12V 3.3
5V 12.2 3.27 Can't test other voltages as I would have to unplug the ATX block and I have no other testing or loading tools
The other voltages came from Motherboard monitor

 

[jonnyGURU]

Voltages look good, and your PC shouldn't be overloading it at all.

What did the voltages used to look like, or is this the first time you've made any kind of observation?

 

[Format _C:]

This is the first time I really noticed voltages had to reset MBM as I lost my settings file in my Format So I had to re do everyt thing again

 

[_Korruption_]

Can't test other voltages as I would have to unplug the ATX block and I have no other testing or loading tools

You don't have to unplug the ATX 20-pin main to get to the +3.3V line. Just stick the black lead into a ground pin, and the red lead can carefully coax it's way into where the orange wire leads to.

 

[Format _C:]

I tested 3.3 It was 3.27 I got it from the aux connector the one that looks like an AT plug. What Color are the wires for -5Volts and -12Volts? thanks

 

[Elec]

You've got a somewhat similar config to mine, and I was apparently overtaxing an Antec TruePower 330 because almost all my current needs were on the +5v rail. My +5v was reading low and causing problems at startup. Yours sounded like the same issue at first, but probably isn't if the multimeter says 5 volts = 5 volts. Also if your board has the auxillary 4 pin 12v connector, it likely doesn't have the massive all +5v load mine has.

 

[MD_Willington]

+/- 5% max ranges:

3.3V +/- 5% = 3.465, 3.135
5.0V +/- 5% = 5.25, 4.75
12.0V +/- 5% = 12.6, 11.4

Don't worry about -12V & -5V...they are legacy shit that some things like the serial port etc can use.

MD

 

[Ice Czar]

Don't worry about -12V & -5V...they are legacy shit that some things like the serial port etc can use.

and more importantly arent used
and without a load on them they are often wildly off from spec
but can be safely ignored, they are typically 1 amp or less anyway

 

[MD_Willington]

To be honest I still use them, although the voltages are used via the PCI serial cards I have...

But if you're not talking MODBUS, DNP etc over a serial SCADA network then nope you don't have to worry about them...



MD

 

[Viperoni]

I had an Asus A7N8X-X and my Epox 8rda3+ both do the same thing: read low on the rail that powers the CPU using the motherboard's sensors, but fine through a DMM. My motherboard tells me the +12v rail is at 11.73v... but I verified that it's at 12.08v.
Similarly, I remember getting 4.67v like you, but the PS was actually at 4.95 or something like that.

Could it be that the motherboard's sensors are measuring the voltage across a load of some sort and it is actually that low in that place?

 

[Oklahoma Wolf]

The Voltages Seem Low even at idle
+3.3 +5 V +12V -12V -5V
3.11 + 4.67 +12.16 -12.16 -5.06

I've got you beat there... my board measures as low as 4.46v when I crank vcore to full and then run the Barton at 2400.

I'll second the advice to check with a meter - my Fortron 530w never goes below 5.09v. And it never goes above 5.10v

 

[jonnyGURU]

I had an Asus A7N8X-X and my Epox 8rda3+ both do the same thing: read low on the rail that powers the CPU using the motherboard's sensors, but fine through a DMM. My motherboard tells me the +12v rail is at 11.73v... but I verified that it's at 12.08v.
Similarly, I remember getting 4.67v like you, but the PS was actually at 4.95 or something like that.

Could it be that the motherboard's sensors are measuring the voltage across a load of some sort and it is actually that low in that place?

Absolutely. Just look at the voltage drop you get just going through a 20-to-24 pin adapter. As much as 1%, right? So what's the voltage drop going to be going through thin traces, through a few components, etc. until the voltage is read by the BIOS?

 

[Ice Czar]

see Ive never gotten a definative answer as to where the voltage readings are taken
I gather it depends on the mobo manufacturer and model,
consider that its also reading the vcore, and that is definately after the mobo's Voltage Regulation Modual(s) (VRM)

are their multople sensors, before and after, does the VRM condition the rails as well as step them down for the Vcore, or simply pass them through for some components (PCI)
is it the same on a majority of boards?

Ive seen 3, 6, 8 phase VRM\PWM
my study of onboard power regulation schemes didnt get very far
and I really need to resume it