-
Competitor rules
Please remember that any mention of competitors, hinting at competitors or offering to provide details of competitors will result in an account suspension. The full rules can be found under the 'Terms and Rules' link in the bottom right corner of your screen. Just don't mention competitors in any way, shape or form and you'll be OK.
How much quicker is a socket 1155 i7 over an i5?
- Thread starter jigger
- Start date
Man of Honour
- Joined
- 23 Mar 2011
- Posts
- 18,699
- Location
- West Side
No difference at all, its only threaded applications that will benefit from hyperthreading on the I7
Soldato
- Joined
- 13 Oct 2011
- Posts
- 11,881
- Location
- Melbourne, Australia
^ This..
It will be quicker in heavy video editing applications (and those alike) but that's about it. It is the same as the i5 otherwise.
Soldato
- Joined
- 18 May 2010
- Posts
- 23,623
- Location
- London
Depends on application.
Gaming would be 0-10% dependant on the game. And there arent too many games that show this difference.
Caporegime
- Joined
- 18 Sep 2009
- Posts
- 30,505
- Location
- Dormanstown.
There might be some minor IPC difference due to cache.
Really???? Assuming the same clock speed....
- For a single threaded app, the only potential difference will be a possible slight increase if the extra cache helps. This will be dependant on what's going on in the rest of the system and is likely to be a negligible performance improvement.
- For apps that have 1-4 threads, the improvement will be subtle at best and only due to the previous quited bigger cache.
- For apps that have more than 4 threads, it will be dependent on the application. Something like prime which just spins in an everlasting loop doing calculations, it will be almost a factor of 2. More meaningful apps - like video encoding - you get an improvement of ~10% but only if the process is compute bound. When I recode video on my i7, the first pass is I/O & interprocess comms bound. It is actually slightly slower with 8 threads compared to 4.
Fundamentally, unless you do a lot of heavy computing that you know will benefit and/or you want i7 vs i5 bragging rights, the i5 is the smart choice (clock speeds excepted of course)...
No not really ard85.
I very rarely convert video and 10%~ +/- performance is pointless anyway.
So in a desktop environment an i7 is the same as the i5. Buying one for a home based system is getting nothing for something and even if you did a lot of AV editing you would see little improvement?
That about sum up the i7?
I very rarely convert video and 10%~ +/- performance is pointless anyway.
So in a desktop environment an i7 is the same as the i5. Buying one for a home based system is getting nothing for something and even if you did a lot of AV editing you would see little improvement?
That about sum up the i7?
Yes.
But you said "Hmm... very differing opinions.". The way I read the replies, it sounds like everyone is saying the same thing so I summarised my understanding.
If you'd have said, "Hmm... not much point then." I wouldn't have posted
I do a lot of converting home videos to DVD and I have found that having HT on, and therefore showing me 8 cores, is hugely beneficial to me having it off.
Plus its placebo I will admit. 8 must be better than 4 after all, but then in the apps I use, it certainly is.
so, in english money, disabling hyperthreading on an I7 turns it into an I5 and so, clock for clock, I would say that no, the I7 is better, but as I said... Only for some apps and in my case, its video processing.
Plus its placebo I will admit. 8 must be better than 4 after all, but then in the apps I use, it certainly is.
so, in english money, disabling hyperthreading on an I7 turns it into an I5 and so, clock for clock, I would say that no, the I7 is better, but as I said... Only for some apps and in my case, its video processing.
Soldato
- Joined
- 13 Oct 2011
- Posts
- 11,881
- Location
- Melbourne, Australia
No, but the performance they yield is (due to them being 10%-15% faster at stock).
A few per cent in games, 30% in well-parallelised apps due to the extra threads and cache.
http://www.anandtech.com/bench/Product/701?vs=551
http://www.anandtech.com/bench/Product/701?vs=551
I'm quite surprised on your suggestion of ~10% speed increase due to hyperthreading for video encoding. In my experience it's a massive improvement of about 80% depending on the codec and application used to encode?
In Adobe media encoder CS6 for instance it can make a big difference, you have to make sure the computer IO can keep up with the encoding, but that's typically not an issue these days.
But 100% Agree that unless you're doing a LOT of video encoding or 3D rendering, going i7 over i5 is probably a waste of money.
E-I
Last edited:
You are only going to see benefits in applications that max out the 4 physical cores, even for example an 8 threaded game will run just fine on a non-HT quad core as long as usage is below 100% (it generally is in games unless heavy number crunching takes place). For example games like Civ 5 which do heavy processing between turns will benefit from HT.
Well.. perhaps I should have said 20% rather than 10%, but definitely not 80% (all my encodes are recodes of HD from the TV). The benchmarks tend to agree too:
http://www.anandtech.com/show/4083/...core-i7-2600k-i5-2500k-core-i3-2100-tested/16
(I chose that as I know it was there).
I use x264 (via ffmpeg) to encode. It's a pretty reference implementation of a modern encoder.
It does. But most tasks most people run cannot be run efficiently as 8 tasks that don't interact and don't fall over themselves. If every app was like prime, then yes, go ahead, but the real world isn't like that
Looking back at those benchmarks, POV and x264 are the ones that stand out as the largest increase in performance i7 over i5. x264 is probably<20% (by the time you factor 2 passes in). POV is 40%ish (but ray tracing is great for being run in parallel). Chromium compile is 50% quicker, everything else basically falls into the ~10-20% mark.