Hyperthreading for gaming

[mad1394]

Does hyperthreading improve performance in games? Can anyone provide any benchmarks comparing HT on and off ? And if there is a difference is it worth the price delta between i5 and i7 ?
Been reading some contradicting opinions on this lately, so I thought it might be a fun topic to discuss.

 

[Vya Domus]

Well first of all you need to understand what HT does to understand what I am going to say about i5 vs i7 or whatnot.

HT doubles some of the front end resources of a core , namely the bits that fetch , decode and decide what instruction is about to be executed. Meanwhile the resources that do the actual computations still remain in the same quantity , in other words all HT does is maximize the usage of a core. Basically under normal circumstances a core remains not fully utilized most of the time , from that you may be able to see why HT would be more effective when there are less cores and less so when there are more in a game that typically manages a limited amount of multitasking.

So it kind of goes like this , something like a Pentium would be worthless without HT due to limited execution resources from the get go , a quad core with HT would generally be faster than one with out (there are some games that will literally not run at 60fps if you don't have at least 8 threads such as AC:Origins ).

Now that Intel finally upped the core count after a decade the importance of HT has been somewhat diminished , but that's only for the time being. At some point it will be more relevant such was the case with quad cores.

Same story for AMD and SMT.

 

[dirtyferret]

Do search, this has been discussed many times and the answer depends on the game but often it's minimal improvement.

https://www.techpowerup.com/forums/threads/4c-4t-vs-4c-8t-vs-6c-6t.241983/#post-3806658

 

[Bill_Bright]

I added my comments to this in that other thread. Thanks for pointing it out dirtyferret!

 

[Vario]

Negative improvement for games. Some games perform the same some games perform worse some perform much worse. There is no reason to get pay money for this technology if all you do is play games. Numerous examples available:
Intel:
https://www.techpowerup.com/forums/...rks-core-i7-6700k-hyperthreading-test.219417/
https://www.techpowerup.com/forums/...70-hyperthreading-test-20-games-tested.216466

AMD:
https://www.gamersnexus.net/guides/2835-amd-ryzen-r7-1700-smt-off-overclock-benchmarks
https://www.hardwaresecrets.com/does-disabling-smt-on-a-ryzen-7-cpu-improves-performance/6/

Do search, this has been discussed many times and the answer depends on the game but often it's minimal improvement.

https://www.techpowerup.com/forums/threads/4c-4t-vs-4c-8t-vs-6c-6t.241983/#post-3806658

The other thread addressing encoding, not gaming. For purely gaming, it performs the same or worse.

 

[mad1394]

The other thread addressing encoding, not gaming. For purely gaming, it performs the same or worse

Thank you. My point is I have been thinking about this lately. Obviously there are a lot more people who simply play games on their pcs than people who work with highly multithreaded applications. I am one of them. I will not encode anything on my pc, so why bother with the i7 8700(k) for example ?
If I were to jump into the 8 series from intel and buy a processor my choice would be the 8600k. The difference in price is better invested in the other components.

 

[Vario]

Thank you. My point is I have been thinking about this lately. Obviously there are a lot more people who simply play games on their pcs than people who work with highly multithreaded applications. I am one of them. I will not encode anything on my pc, so why bother with the i7 8700(k) for example ?
If I were to jump into the 8 series from intel and buy a processor my choice would be the 8600k. The difference in price is better invested in the other components.

That was my logic when I built my machine. You should consider the i5-8400, it runs at 3.8 GHz turbo in games and isn't much different from the 8600K. With the money saved you can get slightly a slightly better graphics card or motherboard. I am also skeptical that ram makes a huge difference on Coffee Lake, having tried mine at JEDEC, XMP, and overclocked and it is hard to detect any improvement. It shows up in benchmarks but I cannot tell when I am playing the game one way or the other.

I would also present the argument that the i5 8400 has minimal downside because the 8700 and the Ryzen 5 2600 main benefits are the 12 threads, but if they do not matter much in games, all of these products are really six cores but the i5 8400 is the cheapest of them and has about the exact same performance for less money.

 

[Papahyooie]

Overwatch makes use of hyperthreading very well, at very high frame rates (144+), I've found through researching the same thing.

 

[SomeOne99h]

There are some posts here before that mention "Smoothness". You can't figure this by benchmarks and numbers.

 

[natr0n]

Depends if game developer implements it. It can help if used properly.

 

[Frick]

It helps if you're doing other stuff at the same time, like streaming. And going from 2c/2t to 2c/4t definitely helps.

 

[Vario]

There are some posts here before that mention "Smoothness". You can't figure this by benchmarks and numbers.

Without an empirical measurement to prove it, I am skeptical. Maybe in the case of the few games that do benefit from it, and there are a couple. But most games it does not show any benefit in terms of frame rate, minimum frame rate, latency, etc.

 

[GorbazTheDragon]

Depends on the games you want to play, per core performance trumps both thread and core count in a lot of cases (basically all the time for older games), on the other hand most cases you are already running beyond 144fps on those games. Some gamers do benefit from higher average framerates due to physics exploits in specific games (ioquake such as call of duty 4) or reducing max frame times/min fps for better smoothness (pro/competitive play). HT can play into the latter by reducing the impact of non game related background processes, but the effect is minimal in most cases. You need to evaluate your use case and whether it applies to you.

If your question is whether to get the 8700k or 8600k, I would say wait until intel releases their 8 core CPUs and reevaluate, there will probably still be some price drops from both AMD and intel.

 

[Bill_Bright]

Without an empirical measurement to prove it, I am skeptical. Maybe in the case of the few games that do benefit from it, and there are a couple. But most games it does not show any benefit in terms of frame rate, minimum frame rate, latency, etc.

I agree and there's good reason for that. Game developers know most gamers don't have such deep pockets to afford the latest and greatest and most powerful CPUs (and GPUs). To make games require such system specifications would greatly limit their sales.

So they code their games to provide good game play on lessor systems.

 

[mad1394]

That was my logic when I built my machine. You should consider the i5-8400, it runs at 3.8 GHz turbo in games and isn't much different from the 8600K. With the money saved you can get slightly a slightly better graphics card or motherboard. I am also skeptical that ram makes a huge difference on Coffee Lake, having tried mine at JEDEC, XMP, and overclocked and it is hard to detect any improvement. It shows up in benchmarks but I cannot tell when I am playing the game one way or the other.

I would also present the argument that the i5 8400 has minimal downside because the 8700 and the Ryzen 5 2600 main benefits are the 12 threads, but if they do not matter much in games, all of these products are really six cores but the i5 8400 is the cheapest of them and has about the exact same performance for less money.

I would pay the 100 euro price difference as the 8600k can go to around 5 gigahertz when overclocked. I think that would be felt especially in high frame rate scenarios.
Of course if the budget is tight then you are correct. i5 8400 ftw.

 

[Mussels]

Does hyperthreading improve performance in games? Can anyone provide any benchmarks comparing HT on and off ? And if there is a difference is it worth the price delta between i5 and i7 ?
Been reading some contradicting opinions on this lately, so I thought it might be a fun topic to discuss.

if you can get higher clock speeds over the HT, always go for the clock speeds (to be extra clear, i'm referring to within the same CPU generation)

I would always choose an i5k over a normal i7, that said this is the kind of thing that really varies between games

Edit: since i saw ryzen mentioned i realised this was about SMT in general and not HT specifically, the main benefit for Ryzen is more bandwidth to the motherboards - you can run more devices at once (like 2x NVME drives) with less features/ports sacrificed.
Intels main advantage is for high FPS gaming, high res (4k) they end up equal - so an overclocked K chip is going to be the best choice for high frame rates. If you arent going down either road (1440 144hz/4k60) then just get whatevers cheapest and you think will last a long time.

 

[slightofhand]

Take some time to do research outside of TPU... this site's members are demonstrably against HT. Do your own homework for the apps/games you use.
Greg

 

[Good Guru]

I've seen on my systems a 15-33% improvement in frames per second, depends on the game.

I got 33% better FPS in Quake Wars. Rise of the Tomb Raider maxed out my i5 4670k at 100% cpu usage. Ghost Recon Wildlands benefits from it if you have 8 threads.

The 6700k is 500mhz faster than it's i5 6600k although with Hyperthreading also enabled it's 40% for Watch Dogs 2.
Watch dogs 2 40%. https://www.gamersnexus.net/game-bench/2808-watch-dogs-2-cpu-benchmark-thread-intensive-game/page-2

 

[cucker tarlson]

depends on the game, but in cpu heavy games it can be huuuuge. Here's what I measured on gtx1080 and 4790k

Spoiler: HT ON - 97 fps

Spoiler: HT OFF - 67 fps

In my personal experience, HT has given me a lot of advantages but hardly any disadvantages. I've seen what some describe as negative scaling, but it was always 1-2 fps, within margin of error stuff,although it should be said that this can happen (just by the way,look at the difference more l3 cache on 8700k makes. Even though 8600k runs 100mhz higher, 8700k with HT off has 4-5 fps higher avg. and min. fps)

https://www.purepc.pl/procesory/test_procesora_intel_core_i7_8700k_premiera_coffee_lake?page=0,42

you may see that in games that rely heavily on single thread performance

Like I said, HT does far,far more than good than harm. Ideal situation is to run an 8700K with HT off, and when you see your CPU usage exceed 70%,which is common in games, turn it on.

 

[John Naylor]

If you are looking to stretch that last 0.1 GHz out of a CPU, I haven't found across the board differences between the i5 and i7. It's not about CPU usage, it's about CPU affinity ... how many cores can it use and 98% of games use less than 4, and 90% barely ever break 2.

However, turning HT off on an i7 would drop ya 7C on SB and that would get us an extra 100-200 MHz. Today, I haven't bothered to try it as with recent generations I have yet to hit a temperature wall when overclcking, the voltage wall usually rears its head before the temps become a real concern.

 

[Vayra86]

Simple rule of thumb: HT/SMT only benefit performance when you lack physical cores or use all of them.

Beyond that, game performance benefits without exception from increased clocks - which also ties into the optimal core count, as more cores results in lower clocks.

As for HT off on an i7, my experience is in fact that it turns the i7 into a less stable and reliable CPU and the gain in voltages or clocks is non existant, definitely not something Id recommend.

 

[Space Lynx]

@mad1394 I'd wait for 8 core no-HT Intel at this point, it's right around the corner, maybe end of year early next year, and it probably will never need to be replaced as silicon/cpu life is ending, and one could argue for gaming being maxed at gpu end of things at 1440p and higher... its already ended for cpu's as long as you have modern one 6th gen and up. I am going to do the 9th gen 8 core 16thread non-k edition, set it to max turbo boost in bios, BCLK to 101.05, and ram to XMP... and as long as everything is stable and temps are great, I will never have to delid. so i am guessing the i9-9800 is prob model number, lol

 

[mrthanhnguyen]

HT will reduce the CPU usage in games such as Battlefield. I don't see any perf improvement at all with HT.

 

[jboydgolfer]

I don't see any perf improvement at all with HT.

By and large that's the case with most games, but there are a few (supposedly) that do benefit from it, at least that's what people post on this site when someone mentions HT doesnt benefit gaming without specifically adding "most", or "the majority" as a modifier. Common sense tells me that 4 threads are sufficient for all games, and in the few cases where more thread's benefits performance , id bet a dollar the benefit is extremely small ,in situations where only the game is concerned (on more than a few occasions, the proponents of HT & its untold benefits to gaming, mention multitasking, and how Game perf is increased by better handling of outside CPU jobs by the extra threads, instead of spreading the 4 threads traditionally thought of as sufficient across the game, and whatever else is running in this hypothetical situation where HT shows its "benefit to gaming").

just to be clear, i dont debate the possibility of an increase in perf with HT, that would be silly of me........i simply advocate that the difference is minute, and likely limited to very specific situations, but across like CPU's, the added threads will make minimal difference if any , in a strictly game performance situation, without added factors like external programs, etc.

 

[mad1394]

I'd wait for 8 core no-HT Intel at this point, it's right around the corner, maybe end of year early next year, and it probably will never need to be replaced as silicon/cpu life is ending, and one could argue for gaming being maxed at gpu end of things at 1440p and higher... its already ended for cpu's as long as you have modern one 6th gen and up.

I do agree that an 8 core cpu from intel with or without HT would be a juicy buy. Depending on how it compares to ryzen at the time of course. God bless AMD for competing.
As a side note on the AMD side I would not consider a processor without SMT. As far as I know most of them have it anyways.