40C idle with a zalman... WTF??

I recently purchased a new motherboard, some lighted cables, and a Zalman CNPS9700. Obviously, I am going to attempt some overclocking. Before I made the changes, my AMD Athlon 64 3000+ was idling at 28C. After changing motherboard and cooler, I am idling at 40C and going to 45C while running Prime95.

Could one or both of my temperature sensors on the mobo be out of whack?

I am confused as to how my aluminum stock cooler was getting lower idle temps than a copper heatsink that looks like a jet engine.

My other problem... For some reason warpspeeder will not let me overclock. In addition, my bios has only 3 OC settings, +1.7% speed, +3.something% speed, and plus 5.something% speed. 5% speed increas falls a little short of the 500mhz or more that I had hoped to achive.

Am I just plain old screwed, or does anyone have any suggestions?

Mobo:
Biostar NF325-A7
Nvidia Nforce 3 250

CPU:
AMD K8
Athlon 64
3000+
2ghz
Venice

Cooler:
Zalman CNPS9700 with blue LED

Memory:
2x512 Super Talent DDR400
heat spreaders

PSU
400 watt
(my 3.3 volt is only running 2.99 could this be part of the problem?)

HDD's
300GB Maxtor Diamond Max 10
320GB Seagate
SATA raid 1

Video:
Sappire Radeon X1650 Pro AGP

Sound:
Sound Blaster X-Fi Extreme audio

OS:
Vista