An Interesting Mining Observation

[Fastbird]

I'm new to bitcoins, caught on and immediately fell in love about 8 days ago.  Finally coming in here.  Anyway, I've been mining on two computers, one a 5750 at about 175 GH/s and the other a 7970 at 650 GH/s.  The computer with the 7970 is my main computer. 

So yesterday, I decided to encode a few blu-rays using Handbrake, which if any of you do this you know it's VERY processor intensive.  My setup (intel I7 950 OC'd to 4.0 GHz, 12 gb RAM running at 1800) normally doesn't go past about 65* C max.  So yesterday I decided to go ahead and fire 50miner up while I was doing the movie encoding given that it is supposed to tax the GPU only. 

Boy was I wrong.

After about 45 minutes, my CPU temps were in the 80-84* C range, and my MH/s on the miner were down and fluctuating pretty rapidly from 375 to 500 GH/s, WELL below my normal rates. 

So I'm curious as to WHY this happened.  I wasn't doing ANY CPU mining.  I turned the mining off and after a little while my CPU temps had dropped back town to about 60-65* C where the normally sit while encoding.  I just wasn't expecting running two different programs set to be task intensive on two different components to have a negative affect on each other like that.

[Gabi]

Yup, this.

The heat of your gpu heated your cpu 

[Fastbird]

Are all of your components crammed inside of a box?

Sounds like you aren't able to exhaust the hot air fast enough when multiple components are being taxed simultaneously.

Components are in a NZXT H2 Classis chassis, side panel off, GPU temps never go above 73*C when mining with the side off.  It's an XFX DD 7970, and the I7-950 is under a Corsair H80 closed loop cooler.

Touche' guys.  I just took a look (it's mining right now) and sure enough, CPU temps are hovering around 50* C instead of my normal idle temps of 38-40* C.  Never noticed it before since I start the miner, walk away, and check in on 50btc from time to time to make sure it's still hashing.