3.5Ghz w/HT vs 4.1GHz w/o HT

[Crawlerz246]

having the relatively new setup of (well you can see in my sig) i7 920 overclocked a little, with hyperthreading ON, and only aircooling I was wondering is there a more optimal OC? right now I have 3.5 OC with HT, so the temps top out at about 70 under full load. I do not want to go higher myself, and I do not want to fry anything trying to overvolt it. I'm not in it to win any contests. I do a ton of online gaming (BBC2 mostly right now), some amature video recoding, and a moderate amount of DVD burning. granted my video card isn't top of the line for playing, but that's a whole different storyline.

 

what I was wondering is this: since HT adds some hefty numbers to the CPU temps, is it really worth it or should I turn off HT and OC more (to about 4.1-4.2 I think was my last good number).

 

thanks for responding, community!

[MrAlex]

4.1 GHz without HT will be LARGELY better than 3.5GHz with HT on. You'll notice a difference in gaming performance too since HT rarely helps in games at all, plus is properly multi-threaded applications, HT will be of no use.

[Waco]

plus in properly multi-threaded applications, HT will be of no use.

That's exactly opposite of what's true - in properly threaded applications HT actually increases CPU utilization (and thus work done) by quite a bit.

[IVIYTH0S]

4.1ghz would be better for most things but not 4+ core optimized programs .

 

Also CF another 4890!

[wevsspot]

Crawler,

 

That's an awfully tough question to answer without a lot of "ifs" "ands" or "buts".

 

For any app that is coded to take advantage of threaded optimizations, HT can make a very positive impact on performance. On the flip side, few games are designed to take full advantage of multi-threading and hence do not benefit any from having HT enabled. With that being said, there isn't much of a performance penalty with it running either.

 

If you ran some FPS benchmarks on one of your game titles you would find that (assuming you don't have a gpu bottleneck) that the higher cpu clocks with HT disabled, would yield higher FPS than running the the cpu at lower clocks with HT enabled. But the % of difference might be the real question here. Would it be significant enough to justify missing out on one of the premier technologies of socket 1366 i7 processors?

 

I struggled with this question a lot when I bought my first socket 1366 rig, ran a bunch of tests both ways, and didn't have a heat issue since I was always under water. In the end I decided that I'd rather run my i7 at 3.6Ghz or 3.8Ghz with HT enabled that to run it at 4.0Ghz with HT disabled. Personal preference, but that is where I landed in the end.

[TheHippi]

Isn't the Frostbite engine one of the few that is multi-threaded? And if you want to find out, just run some tests with and without hyperthreading. That's the only way you will know for sure which will be better for you.

[MercuryDoun]

As far as benchmarks go... HT is worth it. but for games? that rarely use more than 4-cores, 4.0+ghz will be faster...

 

However your example of BFBC2 and its frostbyte engine actually use more than 4 cores. So i think HT would make a good difference there. Hard to say for sure though. I do know that in my testing with 3dmark06 and 3dmark11, HT is worth approx. the same amount of points as a 600mhz OC per core. I have my results somewhere on my computer at home, not even sure if i kept them. But with my CPU at 4.2Ghz with no HT. Got pretty much the same score as my cpu at 3.6Ghz with HT... of course with 4.2Ghz and HT it was much higher, heh.

 

What you SHOULD do, is buy a better HSF, and just keep it at 4.0+ with HT all the time, lol.

 

Ill be honest ive done some pretty extensive testing with my i7-930. I had HT on all the time, and this may be because my 5770 is bottlenecking my CPU. But you would likely run into the same situation as well. I keep my 5770 OC'd 24/7 @ 950/1275, its pretty similar performance to the 4870 and it being overclocked id imagine it competes decently with the 4890 as well. I mean they have the same number of stream processor's and both the 4890 and 5770 share the same stock core clock. and the memory speed is significantly faster on the 5770 over the 4890.

 

In the games i tested, BFBC2, SC2, CoD:BO's, WoW, and AvP. There was minimal if no increase in FPS when i had my CPU clocked at 4.2ghz(With HT) and when it was at 3.6Ghz(with HT) after i did all these tests and didnt noticeable difference in FPS(agian likely due to the 5770 being maxed out) i decided to run my i7 at 3.6Ghz 24/7, which keeps me at 58c max on the hottest core... I mean, all the speed that i can use, and none of the heat on the CPU. So i guess what im saying is... I wouldnt worry about your current CPU speed.

 

Sorry i dont have any proof, i didnt do this for any reason other than for my own curiosity. Some more details that might help you. I played all the games on highest in game settings @ 1920x1080 on a 24" monitor. With ATI settings just on Balanced. So minimal AA and AF. Nothing fancy. But i pretty consistantly get 40+ FPS in all games even at the toughest moments, like explosives everywhere and driving quickly through the area while wildly shooting every which direction. Most of the time i still get 60+ FPS.

 

So... enjoy your CPU at 3.5Ghz... i dont think its hurting anything with your current GPU. But when one day you get around to upgrading it, maybe re-evaluate its over clock. And again if it makes you feel any better, ive also done a similar suite of testing with my i7 @ 4.4Ghz and again, no increase in FPS, just lots and lots and lots of heat, that serves no purpose other than shorting the lifespan of my CPU, so why bother with it?