A-bit EQ ERROR LOG

when ever I have a-bit EQ open while I am playing a game i get A two-tone siren so i set my error log to record and this is what i got.

[Log]
[ErrorRecord]
2005/02/22 12:36:08 Warning:=-12V: -13.02V

So what dose this mean? my voltave on the -12v rail drops 1 v when gamming. My mother board is nf7-s have a starpower psu 430 the stats are
+5v @ 34a
+3.3v @ 26a
-5v @ 0.5a
-12v @ 0.8a
+5v @ 20a
i have 4 fans connected to the 12v connectors, 1 hard drive and 1 cd rom drive. My vid card is nvidia 5700le card it only beeps like that during games. I have my vid card oc and my cpu is oc, cpu is running at 1.7v and vid card is at 1.6v . I have put all the clocks and voltages back to default but it still beeps. The system runs stable it never crashes, temps are cool about 48c max on the cpu.

The reason i am posting is because i want to over clock my system more and about 300 mhz over stock speed my game crashes after like 12 min at that speed, all temps are cool so i am thinking it could be the -12v voltage that keeping me from being stable.
Do i have too many fans running? is my vid card causing the problem?

the negative rails on a power supply are redundant these days and aren't used on a modern ATX board. Are your other rails dropping but not far enough to cause an error noise?

This is just normal no stress
3.3v rail sits at 3.39v
+5v sits at +5.0
-5v sits at 5.0
+12 is at 12.0
-12 is at 12.6
DDR and cpu are fine. I just ran my game and the mobo started going nuts but when i exit the game screen back to desktop it stops. Only the -12v rail giving the troubles its dropping to 13.10 seems to go nuts on the graphix . Dose the vid card use the 12v because in the bios its set to 1.6v