Because I tested Deus Ex on both systems and there appeared to be a consistent benefit of HT in the game, I have conducted additional in-depth analysis of the game with 2 cores, 4 cores, with HT and without HT. The dual-core was the i7-860 at 3.65 GHz, which approximates some of the fastest i3 dual-cores on the market today, and the quad-core was again the i7-860 but at 3.2GHz. I ran the dual-core and quad-core tests at different speeds because dual-cores often run at a higher GHz than their quad-core counterparts.
The number of active cores and the HT state on any i7 can be set within the BIOS. The GPU was a GTX460-768@850, which is equivalent to a ~$120 HD7770, by no means a high-end GPU today.
I ran two identical runs through Hengsha's streets immediately after being dropped off by the transport. I ran down one set of stairs, went all the way around the lower streets, and came up the other set of stairs. I did not interact with NPCs or engage enemies. I simply walked, and yes, I felt a bit like a rat in a maze, but I did it for science. Because there was absolutely no variation between any of the sets of two runs, I did not repeat any run for a third time. Interestingly, there was a significant CPU-intensive spot right below the landing platform, as I passed a chef frying food. Each time the GPU usage would come crashing down,
except on the quad with HT enabled. More information is available in the spreadsheet below.
My results speak for themselves as to the benefits of HT:
Here is the data for Deus Ex:
The following screenshot demonstrates that the quad-core with HT was able to keep the GPU fully-loaded for the entirety of the test. This was not true in any of the other configurations I tested.
I realize there are some people in this thread, and more broadly in the computer enthusiast community, who do not believe that hyperthreading can help a quad-core in any current game. I have conducted all of this testing not because I had an agenda, but because I had a question that I wanted answered and believed there was a lack of information in the enthusiast community and on professional revivew sites. I've already shown that HT does not help in many games, particularly with a single GTX670 in BF3 multi-player, where going in
I was sure I'd detect a measurable difference. I had no idea that Deus Ex of all games would be one that would conclusively show that HT has a benefit not just for dual-cores, but for quad-cores, even in a situation that
should be GPU-limited. I invite others to try to support or disprove my findings, but
unless you are running at real-world settings with and without HT, you are not running the same test, and thus your findings cannot be used to support or disprove the data above.
My findings are as follows: all things being equal, in modern games, HT will either have no negative impact or will have a significant positive impact, especially as to minimums,
which determine the smoothness of the gameplay. The benefit of HT is more pronounced on slower CPUs than on faster CPUs and on dual-cores than on quad-cores. When building a computer, I believe HT is a good investment when taking a long-term perspective on the usage of the system, and in fact, as between a fast dual-core with HT and a slower quad-core without HT, I might suggest the faster dual-core as the more cost-effective solution. Finally, a dual-core without HT simply isn't equipped to handle modern games with even a ~$100 GPU, let alone a higher-end GPU. I would not recommend, for instance, the current Pentiums for a gaming system.