Since upgrading to a GTX280....man the temperature on that thing raised some eyebrows. I dont OC the card at all.
In my old case, with decent airflow, it would still crank up to around the seventy degree mark. Thats freakin hot in my opinion. It increased the case temp considerably. The design of the onboard fan system is ordinary at best on all these cards. Some of the aftermarket air cooled setups are just so much more efficient.
I began using Rivatuner to kick onboard fan into play. For some crazy reasoning, the onboard controller, starts the fan at 40% capacity. Then moves to 60% when warmer, then up to 80% when under full load for a decent amount of time.
Running the fan @ 100% provided a considerable decrease in running temp from start to finish. We are talking 10 degrees. At least.
It seems that I am a complete fusspot when it comes to my temp situation so I recently upgraded my case from a series one Thermaltake Armor (which WERE ahead of their time) to an Antec twelve hundred. Was a big toss up between the Antec or the Coolermaster HAF....similar price point, similar quality of case.
The Antec (or the Coolermaster) have massive airflow straight out of the box. Three fans at the front, two at the rear with a larger fan on top. The HAF has a similar setup, with the same if not more air coming in the front.
Just switching the case over, had a large effect on temps. Most notably I must say, on the GPU. My idle temp on the GTX 280, with an ambient temp of around 20 degrees Celcius is about 47 degrees. That made me smile. Under load, with the stock fan going 100% it peaks at about 55-57 degrees. In my opinion, thats much more acceptable.
Positioning fans blowing on the BACK of the card also helps. But be careful to not block your throughput air.
There are some aftermarket coolers that are just rediculously good for these cards, but you have to be prepared to pull the card apart. I've lost a perfectly good GTS8800 doing this before. They are freakin sensative.
I'm giving serious thought to one of these:
Ultimate CPU Cooling Solutions! USA
Some of the reviews on those are rediculous. Load temps of Mid 30's degrees. Pretty sweet.
Of course there is watercooling.... but I am struggling to justify the cost involved.
Anyhoo...Hope this helped.