View Full Version : Undervolting Power Supply?

01-06-06, 02:39 PM
Hi Everyone,

Here is a question for you tech experts. Can a power supply that is undervolting cause any damage to PC components? If so, what would likely be damaged? CPU, Video Card, Memory, etc? If damage can result then is it possible that a component would still fuction but exibit strange anomiles like graphic or data corruption? Also would it matter how long the system was running with this situation, for example several months or would damage occur within a small amount of time?

The reason I am asking this question is because I just recently found out that my Antec True Power 550 has been running with the +12 and +5 volt rails low. The 12v rail was dipping to 11.855 and the 5v rail was dipping to 4.811.



01-06-06, 02:43 PM
Thats not too bad. Thats completely within ATX spec. ATX spec is 11.40-12.10v

And no, I don't think anything can be damaged. It may cause stability issues however if the rails are dipping too low.

01-06-06, 03:03 PM
Hi Jak,

What if the 12v rail is going up to 12.342?

01-06-06, 03:13 PM
hmmm... that seems a little high, overvoltage seems that it would cause more damage than undervoltage.

I'm not entirely sure though.. I wonder if somebody here has more knowledge on this subject...

01-08-06, 11:37 AM
Thanks for the great feedback guys!

The reason I am asking this question is that I have been experencing some strange graphics anomiles. The problem I am having is jittery, jerky, ghosting graphics not only happening on my desktop but in games as well. When I scroll through text or images in IE, Firefox, Word, etc... the movement is not smooth and is stuttering/ghosting. As well as when dragging a window across my desktop. It gets worse the faster I increase the movement or scroll. If I move the mouse super slow it is nice and smooth with no jitter but as soon as I start to speed up the movement is starts. It not only happens with the mouse but also with the keyboard arrow keys as well. So it is not mouse related.

It's similar to a Vsync tearing, but the text, image, or window has a blurring effect that is jittering or ghosting while its moving and leaves a bit of itself behind that has to catch up with itself. Where with only a Vsync tear you get the stepping tearing but not the blurring that I am getting. When I'm in a game like BF2 or Americas Army, when I turn with the mouse or strafe with the keyboard objects like trees, edges of buildings, other players, etc are ghosting and jittery where again it takes a second for the image to catch up with itself, like a graphics lag.

I just installed an nVidia eVga 6800 AGP into my ASUS P4C800-E. I am running a P4 2.4b, 2 x Corsair 512M PC3200XL's running in duel channel mode, Audigy 2, 2 x WD 120G 2mb HD's, Antec True Power-II 550W PSU, Dell 2001FP Monitor. Before this nVidia card, I was running an ATI 9700 Pro and was experiencing the same problem with that card. I did a fresh Windows XP SP2 install with this new video card, latest Intel chipset drivers, nVidia drivers and all the latest XP updates. I have also tried several older Forceware drivers.

I also tried running another OS using the Knoppix Linux 4.01 Bootable DVD version and the jitter/ghosting was even happening under Linux. So that definatly rules out any problems with Windows XP. I even moved my rig to a friends house to rule out any EMI interference I might have had at mine.

What's really weird about this issue is that my system used to run great, no graphics jitters and smooth like silk. Even when I had my ATI 9700 Pro in it. Then all of a sudden one day several weeks ago it started having this problem. I thought that it may be graphics card related, and anyway it was about time to upgrade my card so I thought that would fix it.

I have tried my rig on two other different monitors - one was a iiyama 21" CRT and the other was another Dell 2001FP. I have swapped out the Mobo for another Brand New ASUS P4C800-E, I have tried different memory, different sound card, replaced the hard drives, replaced the IDE cables, disconnected all fans and optical drives as well as replacing the PSU with a brand new Antec TP-II 550 that is running very tight on all rails.

The only other thing I haven't replaced in the CPU. Is it possible that the old PSU might have damaged the CPU? Or could an Intel processor all of a sudden start causing issues like this? Have you guys ever heard of an Intel CPU causing this kind of graphical problem?

To this point I guess I have eliminated just about everything I could think of that would cause this problem. This should not be happening, my 2D scrolling and dragging and my 3D movement in games should be smooth without jitters/ghosting. This problem really has me stumped.