My 3.3 rail reads as low as 3.15 underload.. What to do???

[robertway]

I am running an Antec True 550 and Have been trying to get a stable overclock on a recently revamped water cooled system using a DFI LanParty Pro875B board, P4 2.4C Rev D1 Stepping 9, and 4 stciks of Geil Ultra Platinum PC4400. I am running into issues with instability using Prime95 if I start to push the FSB past about 210. I've had some decent Prime95 runs at a 5:4 ratio with 275FSB for a 3.3GHz and DDR 433 but this is running the RAM way below spec.

My issue is this, the Geil, according to... well... Geil, needs to run at 2.9 vDIMM which I have it set at. What I am noticing is that according to the DFI monitor and Motherboard Monitor, the 3.3 rail is running at 3.2 when idle and as low as 3.15 under load. I am also noticing that If I set vCore at say 1.75 for example, underl load it is reporting at as low as 1.68. I know I still need to put a multimeter on the system to get real reading at idle and under load, but assuming the readings are correct, is the low running 3.3 rail a probable culprit for my getting the Geil to run at spec. If yes, is it time for a new PSU or is there something I can do, without risking death, to get this one in line.

Thanks in advance,

Robert

[Susquehannock]

Since the true control has the front panel controls, I assume
you have the true power. Am I right?
If so you may need to open it up to adjust the 3.3v rail. That's what is nice
about this PCP&C unit. You can adjust the rails from the outside and
not void the warranty. :)

[robertway]

You are right in that I have the Tru Power, no xternal rail controls. As far as opening it up and adjusting the rail, I have quite a bit of reading to do in the forums here before I tackle that but I learn pretty quickly. With the situation I laid out above, am I on the right track in hunting down my issue, is there a way to see what the real-time vDIMM reading is as I'd like to see how far the 2.9v setting is being fed to the Geils.

Thanks in advance,

Robert

[robertway]

OK, I picked up the 20 dollar multimeter from Home Depot and I measured the 3.3v rail at the motherboard connector as well as at the aux connector, the orange cables. It is reading dead-on 3.3v. Actually it is 3.31 at the MB and 3.35 at the aux when idle and only falls 0.01 to 3.3/3.34 when I start Prime95. Now Motherboard monitor and the DFI hardare monitor (came with the Pro875B board) are both reading the 3.3 rail as low as 3.14 under Prime95. The other rails measure within .03 of the multimeter in the MBM5 and DFI utilities.

Now I'm confused, I expected the 3.3 rail to be running low when I read it with the multimeter, but it is dead on. Is the motherboard just hosing up the 3.3v, I've read some post around the forum about ASUS boards having crappy 3.3v regulation. Is there any way to determine in real-time what is being fed to the DIMMs, to see if they are actually getting the 2.9v I set them at.

any suggestions would help

[Dragonprince]

Software utlilities are not accurate and should never be used, period. They draw their readings from the motherboard. These readings which will change with temperature and load on the motherboard. Just as CPU socket heat diode sensors are notoriously off the mark so are the other board sensors. Only a multimeter will tell you the whole truth and nothing but the truth...

[robertway]

Point taken about the soft utils, my concern is that since I'm seeing the 3.3 rail dead-on with the multimeter, how can I make sure the MB is handling it correctly and giving the vDIMM the 2.9v I am setting it at. The Geils are power hungry with 2.9, at least, to run em at spec DDR550 and if the MB is just a bit off handling the 3.3 coming in I can see where the Geils are getting their instability from.