recently installed an 8800gt an began receiving system crashes, initially thought the card was to hot but now ive did some research and someone has mentioned that installing a new more powerful video card can also increase CPU usage and in turn heat, which also increases ambient temperature leading to a nasty chain reaction and a system crash. I'm using hardware monitor while running prime 95 and this alone is putting my CPU to 79 degrees. This is approaching safe limitations an x2 6400 isnt it? When I stress test the card and the cpu the system crashes.. im using stock coolers but this still should not be happening my system is well ventilated. any tips or possible other reasons for this problem?

another note, amd recommends ambient temps dont exceed 53-57C or something, im not sure if im reading this correctly but hardware monitor TMPIN1 says 34c and under TMPIN2 says 60C.. is that ambient temp because i put my hand in my case and it is not 140 degrees F. ambient temp under riva tuner monitor is climbing just above 50, possibly higher.

I'm an Intel user and AMD is a bit different but 79 is way to high. Also check your CPU is strong enough. 19 amps for the GFX rail and it should also be at least a 350W PSU.

79 is seriously high, you want to aim for less than 60.....maybe 65 when its being absolutely ragged ie orthos prime

check to make sure that your cpu fan is seated properly. also, check that the 8800GT isnt pushing a lot of hot air into the case with nowhere to go. if that hot air is just sitting there, the temperatures of everything will go up. maybe just another case fan will get the job done.

79 is too high for any CPU. You will definetly will be getting errors and system crashes at that temp. You have cooling problems to sort out.

Yes, your temps are too high, however, in order to provide you with meaningful assistance, more information is required;
1. What case and cooling do you have (case fans etc)
2. What CPU cooler are you using, what mobo
3. What is the ambient room temp (use a regular thermometer to measure room temp).
4. What power supply are you using
Answer those questions, then maybe we can start providing some useful suggestions.
** Also indicate cpu voltages, and if you are overclocking the system at all.

Raidmax Smilodon 4 80mm case fans 2 blowing in on the cpu one blowing in on the HDD's and one blowing out the rear, Stock AMD cooler (arctic silver). Stock 8800gt cooler (put arctic silver), stock little mobo chipset fan. 73-79 ambient in the room. 550 watt dual 18 amp 12v rail rosewill PSU. 1.4 voltage. No over clocking everything is stock which is why i'm baffled. Even when the case is wide open to outside air the CPU hits the same temp what is going on? (basically without a case the cpu is still frying??) If I place an 80mm fan right next to the cpu heatsink blowing away from it i notice slight temp drops.. whatever this indicates.

this is ridiculous my cpu fan is running at 1200rpm when my cpu is idling at 46c,could it be that my mobo doesn't support the faster chip and doesn't know how to run the fan for it? i upgraded from an x2 3800 to an x2 6400 on a biostar tforce 550, I did some research and figured it was fine...plugged it in and it worked flawless until the 8800 gt came into play.

hmm, Tried switching motherboards and cases.. no change, it may have even got hotter, took the side off the case put a large fan blowing directly in, dropped ambient temps several C, and this resulted in the gpu cooling from 85C to 76C under stress testing.. CPU still up at 83C even with a huge fan on high power blowing into the case... can anyone help... this is the worst problem ive ever had and ive been working on it for 4 days without change.