I'm looking at getting a new heatsink+fan for my 9800 pro 256. I've heard that they generate gobs of heat, because the bulk of memory is on the top of the board. I don't know if this is true, so that would be my first question. My second question would be, If it does generate a lot of heat, what is a good heatsink+fan? I've been looking at some of the zalman heatsinks, but I know there are others that are probally just as good. Any suggestions?

They generate lots of heat because ATI managed to clock them extremely high for the design. *applauds ATI*

There are others as good as zalman of course, but what they do well is make things quiet without sacraficing performance.

You don't really need a fan. I run watercooling, so it doesnt really affect me, but theres a sink, (which i cant find a link to for the life of me) that is just a huge bit of copper with heatpipes. Youll need about a gallon of thermal paste for all the area it fits over, but it will cool a card very well.

---example: Both me and friend of mine have the same card. (9600se, 5600xt) He got this cooler, i still had my stock sink and fan. since mine wasnt cooled properly, i was generating about 3 times as many tiney errors as he was, which each had to be corrected. This made him be able to play doom3 in 800x600 with no jerks, and poor me was still in 640x480. ---

ah found something similar to his, Kingwin VGA cooler . The only problem being you may have to reinforce your card afterwards, due to the huge weight.

ALSO.... add extra case fans.

The greater the difference in tempreture between the air the fans are operating on, and the hot surface, the more efficiant the cooling is.

But by adding more case fans, the system tempreture significantly dropped, this making the existing cpu / graphics fans even cooler.

Aye, the colder the outside of the copper plate is, the more it will pull the heat from the core. Use large casefans, 120mm or so, to be the quietest. Im assuming quiet is a factor, rubber gaskets make all the difference, stopping vibration. Rubber standoffs on screws, rubber gaskets around the fan, putting rubber pads under the case. All can make it much quieter, and are like 2$ for some scrap rubber.

i have a 128 mb 9800 pro and i havent had a single problem with it

you probably wont need one as long as you dont plan on overclocking your card

larger fans are also louder

depends on the fan speed.
a large fan on a slow setting will move the same amount of air as a small fan on a high setting,
and cause less noice.

its like 2000cc a car engine on tick-over is more powerfull than my model aeroplane 9cc engine running flat out... but the car engin is much quieter, even though it 20 times bigger.