Adjusting fan speed, how fast should temp drop?

Ok. I just noticed something odd with my rig tonight.

I haven't messed with any setting on this rig for about 4 months, and tonight I was going to try again. So, I cranked up the 2 channels on my Sunbeam rheobus that controlls my 2x120mm Delta SHE fans........and this is when I noticed it.....

Atm, I only have the ABIT uGuru monitoring software to rely on for temps, and the BIOS is reading damn close to what this program is showing. Same with say MBM5.

Not even 2 minutes after putting the Deltas on full blast, I noticed a 5-7*C drop in temp on the CPU. Uhm.........is this posible? I'm thinking no, as my rig isn't THAT efficient, and I don't know of any that are......

Here's what I got:
Swifty 6002-775
Swifty MCP-650
'77 bonnie HC
2x120x38mm Delta SHE fans on a Sunbeam 4 channel rheobus.

Right now, the system is reading 32*C, and the CPU is at 23*C. I have a digital thermometer in my room on the other side, away from the comps, and it's reading 23.3*C.

What's going on, folks?

A minor update.......the system is currently fluctuating between 19-20*C atm......with a room temp of 22.8*C..........heh?

More air to disapate heat faster results in lower temps, though your temp sensor is probaly off quite a bit. EITHER WAY it's still a nice drop.

UGuru reads the temps just like the bios so they should be the same

Yeah, your digital room thermometer is probably off--you won't get below ambient with water. But, even getting close is quite an acomplishment! Congrats!!!