Solved Low 12 volt rail Tags: Power Supplies Computer Shutdown Components Last response: March 16, 2010 2:34 AM in Components Share skikarl March 4, 2010 12:35:28 AM a computer of mine keeps randomly shutting off, then turning back on and loading back in. it does not tell me that windows has not shut down correctly or anything. i suspected 2 things overheating psu checked the temps, all good checked the psu with my psu checker, all good. looked in bios, and the 12v rail was at like 11.1-11.3. is that voltage acceptable, and it was jumping around there ALOT. More about : low volt rail | E-mail me updates | Report abuse Register or log in to remove Best solution GhislainG Power supply Authority March 4, 2010 2:14:21 AM You should use a DVM to check it, but 11.1-11.3V is out of specs. It should be 11.4-12.6V and relatively stable. | Report abuse JackNaylorPE Power supply Master March 4, 2010 2:25:39 AM Brand / Model ? | Report abuse cjl March 4, 2010 4:12:22 AM That voltage would be out of range, but I would check it with a digital multimeter first. Software and BIOS readings are somewhat notoriously unreliable. | Report abuse Related ressources Help With A Low 3.3 Volt Rail - Forum 12 volt rail seems weak? - Forum 10.30v on + 12volt rail - Forum Radeon HD 5770 on 25 amp. on 12volt rail ? - Forum + 12 Volt Amp Rail Confusion - Forum Ask the community Publish jsc Power supply Master March 4, 2010 4:23:59 AM Like the other posters above said, "11. - 11.2 volts is out of tolerance." But is is probably worse than you think. Remember, a PSU tester puts a minimal load on a PSU. Borrow a meter and check between the yellow and black wire on a drive molex power connector while the PSU is running. With a little over 11 volts, a good PSU would not have let you boot. | Report abuse ronss March 4, 2010 7:46:19 AM tolerance on a psu is 5%, so you should have 11.4 v +.....also, check you heatsink and fan...do you have thermal paste under the heatsink or pad...is the fan running properly | Report abuse Onus Power supply Master March 4, 2010 3:35:15 PM Full system specs might help to see if you're overloading your PSU, and also its brand and model to help determine overall quality. | Report abuse skikarl March 5, 2010 12:03:35 AM ok...so, the first post answered my quest. and as far as overheating, its not. and i own a DMM, 3 actually, im not a tech noob. and the voltage i posted was already checked with my multi meter. | Report abuse cjl March 5, 2010 12:37:04 AM If it's reading <11.4V with a digital multimeter, it's out of spec and should be replaced. | Report abuse skikarl March 16, 2010 2:34:20 AM Best answer selected by skikarl. | Report abuse Register or log in to remove Ask the community Publish Tom's Hardware>Forum>Components>Low 12 volt rail> Related ressources: ForumVoltage on the 12volt rail Forum+ 12 Volt Rail Amp Rating ForumStupid question about 12volt rails. Forumi have 2 , 12 volt rails do the amps combine or can i combine them? Forum12 v rail low for shuttle power supply ForumAsus Probe Giving Alerts on 5 Volt Rail ForumLow voltage on 12 v rail ForumPSU for GTX 660 SC Signature 2 (24A on + 12Volt rail ) ForumPentium 4, 5 volt rail indicates low Forum12 volt rail - someone explain please Forum7770 and 650Ti 12 v rail Amps compared to my PSU ForumWay to put 3pin fan to PWM? ForumHigh Base Clock/Low CPU Multiplier ForumCPU Reading Low Forum+12v Rail showing 8v on two PSUs More resources Read discussions in other Components categories Power supplies Sound cards NICs Akasa Antec Cooler Master Cougar DeepCool Enermax !