Athlon XPs aren't supposed to run dual, you have to get Athlon MPs for that. XPs might work, but they probably won't, and it's really not worth the risk anyway.
If you're looking for a good heatsink on a budget, the Thermalright SK-7 (doesn't come with fan, takes 80mms) and Spire FalconRock II are both good choices. If you can afford to spend a little more, go for a Thermalright SLK-900A (doesn't come with fan, takes 92mms).
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DEC Pentium X2 5200+ w/ HyperCache (Ezra core)
Asus M7NCD-MAX3 (OPTi Vendetta 82C760)
6x Generic 32MB PC2700 RDRAM (50ns SIMMs)
2x nVidia Millennium X1800 Duo (SLI mode)
12x (daisy-chained) Quantum Medalist 180GXP (w/ separate SCSI-1 adapter)
"Oh, you started a Rube Goldberg machine. A Rube Goldberg machine... called JUSTICE." <a href='
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