Dual Processor Dual Core Xeon 5160 - 3.0GHz (Woodcrest) - 2 x 4MB cache or Dual Processor Quad Core Xeon 5345 - 2.33GHz (Clovertown) - 2 x 8MB cache which one is batter and stronger for huge traffic
The higher cache is only useful for complex processing. Simple http page serving consumes very little resources. So, if you have a complex and large dynamic site, then the higher cache of cloverton would benifit you more. Also the quad core is always better than a dual core! I think the cost is also high for the cloverton.
definitely Dual Processor Quad Core Xeon 5345 - 2.33GHz (Clovertown) - 2 x 8MB cache if still interested