multiplayer lag problems on starcraft 2

I just bought a new computer and I've found that when I run SC2 I lag terribly after 1-2 games and eventually dropped. This only happens when the graphics are set above low. I should be able to handle the game on ultra settings. I sometimes lag even on the lowest settings while my 5 year old laptop doesnt have that problem. Sometimes the system will reboot when its overwhelmed. Here are my specs:
Intel i7 3.07 ghz
Nvidia Geforce x465
windows 7 64 bit
6 gigs of ram

I updated my video card driver and my fps is about 60. Also, while watching one of the movies on high in sc2 my computer rebooted. Before, I wouldn't be able to log in to bnet because it said I had a connection problem but once I opened firefox, I would log in. When any new information was needed, I would have to refresh a webpage and suddenly bnet would work for that small window as well. Don't know if the two are related or are separate issues. Help is much appreciated.

 

Download and install hwmonitor
and see what the temps etc are. Download the 1.17 setup, english on the righthand side.
....take a reading when not running the game CPU(core) and GPU Video card and post them. (Just a screenshot of results is fine)

Then run the game for 10min or so and take another reading post the results

 

Without running SC (all in Celsius)
Value-Min-Max
Temperatures:
TMPIN0 32 32 33
TMPIN1 73 72 76
TMPIN2 48 48 49

Core Temp
Core 0 35 34 40
Core 1 32 31 38
Core 2 36 35 42
Core 3 28 28 36

NVIDIA GTX 465
Assembly: 28 28 29
Voltages: .88 .88 .88
TMPIN0 37 37 38

This is while running SC2 on medium graphics:
TMPIN0 38 32 38
TMPIN1 82 72 83
TMPIN2 49 48 49

Core temp
Core 0 39 34 49
Core 1 36 31 47
Core 2 40 35 46
Core 3 34 28 43

NVIDIA GTX 465
Voltage: 1.00 .88 1.00
Temp: TMPIN0 57 37 58

 

Here they are. Sorry didnt realize I could attach files

 

Temps seem OK.

maybe a hint that if you run the games on low it is OK.....I would think your video card maybe having problems

Try lowering the screen resolution and see