I'd probably trust the Zalman over the Blue Orb, though that's probably from reading reviews from years ago when the Orb was out performed by the stock heat sinks of the day.
I just took the 9500CU plunge, should arive in a few days.
but im told tha tcopper "attacts" heat and aluminum dissapates heat faster if thats the case the Blue Orb should preform better than a Zalman all copper or Aluminum/Copepr versions
From a chemical issue, Aluminum simply is more resistant to thermal change than copper, so Copper will transfer it faster, either moving it from the core, or disipating it into the air.
From what I've read on the 2 both are very good, I'm not a metallurgist but reading the reviews suggests that cooper is used to absorb heat while aluminium is better for transferring the heat. I also like the fact that the fan also blows over other motherboard parts like the mosfets aiding in passive cooling.
I've got the blue orb on order for a system build but I think down the track I'd like to try the Soniq Tower 120 all the reviews I've read on this one is one are very high.
From a chemical issue, Aluminum simply is more resistant to thermal change than copper, so Copper will transfer it faster, either moving it from the core, or disipating it into the air.
bront is right here. copper is a better conductor than aluminum therefor transferrs heat faster. aluminum is a decent conductor otherwise companies wouldnt use it to make products that dissipate heat. copper is heavier and more expensive due to it being more "rare" to find. personally i dont think you could go wrong with either but these guys posting about the difference between "transferring" and "absorbing" heat need to go and retake high school chem. its all about conduction and copper rules there, cept to gold, but that would be a little out of budget.
im kinda late but id suggest the blue orb... i was considering that zalman, and went to actually hold it before i got it... that thing weighs like over a pound. and just think, its constantly pulling down on ur socket, i mean it may be uncommon but it could rip out ur cpu, if u have a decent brand name mobo i doubt it will happen, but if u have a cheap chaintech like me id stay away from copper... just cause it helps me sleep better at night ... but also keep in mind the blue orb has a 120 mm fan, making it massive, that will most likely make u have to keep memory out of bank 1... so if ur using all memory banks, consider a smaller heatsink. i hear thermalright makes a pretty sweet alunimum heatsink