I think that's the whole point though - if something like a 92mm Nexus on an XP-90 were already capable of cooling, say, a (non-overclocked) Conroe while still running slow enough to be effectively inaudible in a given system, then there'd nothing to be gained by using an Ultra 120 or a Ninja, as it wouldn't be "more inaudible" whatever you did with it.
Exactly. For instance, if we take the massive heatsink phenomenom to the extreme and turn the whole case into a 14kg heatsink ala
the Zalman TNN-300, SPCR gets CPU temperatures in the 40 C through 50 C range (fully passive). Specifically, using their CPUBurn run (for equivalence to the way they measure temperatures in heatsink reviews) gives a temperature of, essentially, 51 C regardless of added fans Zalman TNN-300 Fanless PC Enclosure System
SPCR's review of the Scythe Infinity gives CPU temperatures in the range of 42 C through 53 C depending on fan voltage and orientation Scythe pushes towards Infinity
Their review of the Thermalright Ultra-120 gives a range of 39 C through 52 C, depending on fan voltage Thermalright Gets Back on Top with the Ultra-120
The Zalman CNPS8000
ranges from 49 C through 60 C.
The Arctic Cooling Alpine
runs from 53 C through 65 C.
The Spire Verticool II SP601B3
runs from 42 C through 69 C.
The Arctic Cooling Freezer 7 Pro
runs from 39 C through throttle
(about 75 C for the processor used).
And, thanks to a table in the Arctic Cooling Freezer 7 Pro review, the stock Intel HSF
runs from 52 C through throttle
, the Scythe Ninja w/ Nexus 120 fan runs from 40 C through 50 C, and the Thermalright XP-120 w/ Nexus 120 fan runs from 45 C through 68 C.
Except for the Zalman TNN-300, it looks like all of these measurements were done on the new socket 775 test system (P4-2.8 Prescott, 1 MB cache, 800 MHz FSB in 775 casing, Thermal Design Power is 84.0W, Maximum Power, as calculated by CPUHeat & CPUMSR, is 100.76W). The TNN-300 uses an Athlon 64-3000 (Venice core). So how those numbers compare is beyond me.
The point is that on the test system (Prescott), 75 C is bad (since the CPU throttles), and 52 C ought to be OK (since that's where the stock Intel HSF runs at full fan power). Since this is Silent PC Review, assume we want the lowest fan speed and a temperature no worse than OK. Then, the Ninja, Infinity, or Ultra-120 are all fine. But, where's that "OK" point with the Conroe Core 2 Duos like the E6700? What's the throttle temperature? If the TDP of the Prescott is 84W and the Core 2 Duos is 67W (about a 20% drop), can we assume all heatsink temperatures will drop about 20% (say, 10 C)? Is temperature change linear with power or is it something like a square or square root? Making the silly assumptions that the OK temperature and throttle temperature will be the same as with the older chips, and all heatsink temperatures will drop 10 C at any setting, then just about any heatsink will do, regardless of fan speed. The problem is, those ARE silly assumptions. But, I've seen nothing to give me any better data.
Sorry for the long rant.