You can also buy purpose made fans for video card cooling. Don't really know much about them, but I'm sure some other guys around here can help you.
Personally, I'm running a 120mm case fan blowing down on my V3, and I'm running at 175 with it. I also had problems @ 166 without cooling.
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PII 266 @ 448, 64MB of 66MHz SDRAM @ 79, Aopen AX63 Pro, V3 2000 @ 175, 13.6GB - 7200rpm WD Expert, SB Live Value, LG 40x CDROM, Jazz 300W Front Speakers + Sony SRS PC300D Rear Speakers / Sub Woofer, 15" Monitor, Full Tower Case, Win98 Original Edition.