PSU bad?

Here are my bios volt. readings;
+12v ---- 12.224
+5v ------ 4.838
+3.3v ---- 3.248

The problem is that during boot up first thing in the morning my bios does not see my hard drive. The error message pops up during the dmi pool screen loading and says, media failure, check cable. This is an Antec case with a 400 watt power supply. I have had this case for about a year. I replace my a7n8x dlx 1.6 with a 2.0. before the rebuild I had no problems, but since I have had this one. I replaced cables, mb battery, mb drivers, flashed with diff. bios, and even reformatted. I even tested the hd for good measure. I have come to the conclusion that when this power supply starts to go bad it puts out less voltage when cold. After it runs for a few minutes, I can get it to reboot and see the hard drive. Once it starts up, I can turn it off and on at will throughout the day without incident. Do you think my psu is going bad? Is there any way I can test it without removing and trying a known good one? I remember my +5v reading was around 4.91 - 4.95, but now it is 4.81 - 4.83. I replaced the board and the 2100+ I had with a 2500+ Barton. That is the only difference. It is only the hd that is not seen. Thanks in advance.

Weird. Might it be Harddrive failure? You might want to try scanning the harddrive with Windows' disck checker. I don't think that your voltges are low enough to cause a problem like this, and if you have added more power-hungry components it could explain the slight voltage drops.

If you suspect your PSU is to blame you need to measure your rails with a multimeter. The difference in the readings from mbm from your old board to the new might just be a difference in the motherboards and their voltage regulation.

I wonder if there is not a problem with your motherboard. Try moving the HD onto the other ide channel and see if it still happens.

Stupid question for you Deathknight: Where is the read point for the voltage rails with a multimeter on this board? I just got my multimeter, and am very keen to test all my voltages

The answer is probably a blantently obvious one (*I am ashamed at my lack of knowledge*)