cody379,
Usually when I post something, I try to speak based on my experiences (or at least something that can be closely related to the hardware I have personally tested & experienced).
Unfortunately, both CPUs you mentioned are pretty high-end ones and rarely seen (more often, I get to test the more common hardwares, not \"exotic, high-end\" stuff.)
In particular, I haven\'t personally tested a Pentium D 3.6 nor P4 3.8ghz, so I don\'t have any hands-on experience on them. (I have diagnosed a Pentium D 815 or was it 820, and it was only once before -- the Pentium D-9xx series is an improvement over the Pentium D-8xx series, but I don\'t have personal experience with the 9xx series)
I have tested a number of Pentium 4s (Williamette, Northwood, Prescott), but again, I haven\'t any hands-on experience with the high-end Pentium 4-672 3.8ghz either. I\'m not sure if the LGA775 Pentium 4 Prescott-2M will resemble P4 s478 Prescott or not in terms of performance)
With that disclaimer out, I\'ll offer my own opinion (may or may not be right), based on what I recall from what I\'ve read from web reviews about Pentium 4 and Pentium D in general.
* I tried searching for P4 672 and P-D 960 but cannot seem to find comparative reviews pitching one processor to the other.. :(
There are only a few separate reviews for the P4-672 and somewhat more for P-D 960, but not being compared at the same time.
For instance, here the P4-672 is compared with Athlon 64:
<click here for link>
And here, the P-D-960 is compared with Athlon 64:
<click here for link>
The Pentium 4-672 (tested in above review is the P4-670 which is almost similar to the 672) is benchmarked to be slower than the Athlon 64 X2-4800 but comparable or faster than Athlon 64 X2-4000.
Whereas the conclusion for the Pentium D 960 performance puts it between an Athlon 64 X2-4600 and Athlon 64 X2-4800.
<click here for link>
My opinion then is that there shouldn\'t be too different performance for the P4-672 and P-D-960 in terms of single-threaded performance/games.
However, once multi-threaded apps are taken into account, the P-D-960 will most likely come out ahead, notwithstanding the HyperThreading feature of the P4-672.
But then again, I would place my money not on any of those two power-guzzling processors, but on the more power-friendly Core 2 Duo series.
For instance, take this example (GTA IV performance with different processors -- the Pentium D 960 is benchmarked here, along with a variety of Core 2 Duos, Pentium Dual Cores, up to the 1st-gen Core i3s).
Notice that in GTA IV, the Pentium D-960 (3.6ghz) performs similarly to the Pentium Dual Core E2200 (2.2ghz) or Core 2 Duo E4400 (2.0ghz).
(The PDC and C2D have much lower power consumption).
You asked about the QX6700 and QX6800, both processors are also very high-end ones at the time of release (again, I\'m not able to get my hands on such expensive processors -- as I typically only get to test the common mainstream/entry-level hardware). But based on the GTA IV (which is quite a CPU-intensive game) benchmark, you can see that both perform similar but slightly less than a Core i3-530 (note that Core i3-530 is a lot more power-friendly again).
-- edited by dta on Mar 06 2012, 12:30 AM