Sign in with
Sign up | Sign in
Your question

Odd Reading on the +12V Rail

Last response: in Components
Share
August 15, 2010 3:57:28 PM

Hello,

I noticed that Speedfan reads the +12V rail as 4.75 to about 5 V while on idle. On full load (during stress test) it jumps back to normal 11.89 to about 12.49 V. Got the same exact readings on CPUID Hardware Monitor and Everest.

I have tried two power supplies, Kingwin LZG-1000 and Sparkle 1000 W, and the results are the same.

If both power supplies are functioning correctly, then could it be my motherboard on the 20+4 pin or the 8 pin EPS?

More about : odd reading 12v rail

a c 139 ) Power supply
August 15, 2010 4:02:50 PM

Hello Admiral_Cecil;

Those software utility programs are semi-notorious in reporting inaccurate voltages.
Does your MB BIOS or motherboard utility software show the same values?

The 12V allowable spec range is plus or minus 5 percent (min 11.4 / max 12.6).
m
0
l
a b ) Power supply
August 15, 2010 4:02:55 PM

I wouldn't trust Speedfan, if your system is stable then nothing should be wrong.
Software readings (Especially speedfan) do sometimes give inaccurate readouts, try using a multimeter if you really want to find out the voltages.
m
0
l
Related resources
August 15, 2010 4:08:47 PM

Hello,

Yes, the bios is reading all the rails +3, +5, and +12V within the +/- 5% as you mentioned.
m
0
l
a c 139 ) Power supply
August 15, 2010 4:14:52 PM

I'd put my trust in the BIOS readings.
Since you've tested two PSUs and got the same results I think you're in good shape.
m
0
l
a b ) Power supply
August 15, 2010 4:45:18 PM

your computer wouldnt boot if there were 5v on the 12v rail. but anyhow many software monitoring programd (esp speedfan are unreliable)
m
0
l
!