Intel i7 vs i5

scottcmbel said:
This is the spec im currently going with iv got half the part apart from cpu/ram/hdd
Click to expand...

If you've already got an X58 mobo, it's too late - you have to go for an i7! So splash the cash and enjoy :). But you could have gone i5 760 as the i7 is no faster in gaming than i5 7xx, in fact a tiny bit slower. The saving could have got you a better GPU and/or SSD. But never mind.
 
Liampope said:
If you've already got an X58 mobo, it's too late - you have to go for an i7! So splash the cash and enjoy :). But you could have gone i5 760 as the i7 is no faster in gaming than i5 7xx, in fact a tiny bit slower. The saving could have got you a better GPU and/or SSD. But never mind.
Click to expand...

:D:D Love the way you let them down gently. :p
 
Hee hee :)

Well it's not like owning an i7 is some kind of disaster is it? :) Could have done more homework, but I think any regrets he might have will soon disappear, and the hole in his wallet will heal over time :)
 
Is that really true? An i5 beats an i7 for gaming? Where does an i7 shine then? Especially on the x58 chipset?
 
i5 beats i7 is clutching at straws really - lets just say they're pretty much the same. i5 has an on chip PCIe controller so has a very small gain over i7 with a single GPU. Stock speed benches will show a slightly bigger lead for i5 because it has a more aggressive turbo boost. Overclocked to the same fixed speed (no turbo boost) they are about the same.

i5 and i7 are pretty much identical. i7 has three extra features that you're paying quite a lot for...

Tripple channel RAM - higher memory bandwidth than dual channel. Shown to be worth pretty much nothing in gaming and most other apps because, basically, dual channel isn't currently a bottleneck.

Full 16x/16x SLI/x-fire - i7 can run dual GPUs both at full 16x PCIe speed. i5 can only run dual GPUs at 8x/8x (although high-end P55 i5 mobos have an extra controller chip allowing 16x/16x, but if you're spending that much, you may as well have just bought an X58 i7 in the first place). Benches show 16x/16x is worth about 1-2% performance gain if using dual GPUs, i.e. x8/x8 currently isn't a bottleneck.

Hyperthreading - the ability of an i7 quad core to pretend it actually has 8 cores. The pretend cores can efficiently utilise the scraps of spare time the real cores dont use. This is the only i7 feature that shows real performance gains. In heavily optimised multithreaded encoding/number crunching type apps, hyperthreading can be worth up to 25% performance gain. It's usually much less gain, and is 0 gain in games. Due to the way games are coded they are never likely to see that full 25% gain from hyperthreading, even if they are optimised to make use of it. Even if they do, that's 25% performance increase for a 50-60% CPU price increase, plus a more expensive mobo.

IMHO i7 just aint worth it unless you're using those apps that actually benefit from hyperthreading, and your time is money. Otherwise i5 is a much better bang for buck choice, which is why I got one :)

Oh yeah - with X58 there is the six-core i7 as a potential upgrade. But the reality is the 980 will remain ridiculously priced until it disappears. By the time six-cores are needed in gaming and people's AMD/i5/i7 quads are struggling, there will be mainstream six and probably eight-cores available cheaper than and outperforming i7 980. So imho forget that as an upgrade path and good reason to go X58.
 
Last edited:
Liampope said:
i5 beats i7 is clutching at straws really - lets just say they're pretty much the same. i5 has an on chip PCIe controller so has a very small gain over i7 with a single GPU. Stock speed benches will show a slightly bigger lead for i5 because it has a more aggressive turbo boost. Overclocked to the same fixed speed (no turbo boost) they are about the same.

i5 and i7 are pretty much identical. i7 has three extra features that you're paying quite a lot for...

Tripple channel RAM - higher memory bandwidth than dual channel. Shown to be worth pretty much nothing in gaming and most other apps because, basically, dual channel isn't currently a bottleneck.

Full 16x/16x SLI/x-fire - i7 can run dual GPUs both at full 16x PCIe speed. i5 can only run dual GPUs at 8x/8x (although high-end P55 i5 mobos have an extra controller chip allowing 16x/16x, but if you're spending that much, you may as well have just bought an X58 i7 in the first place). Benches show 16x/16x is worth about 1-2% performance gain if using dual GPUs, i.e. x8/x8 currently isn't a bottleneck.

Hyperthreading - the ability of an i7 quad core to pretend it actually has 8 cores. The pretend cores can efficiently utilise the scraps of spare time the real cores dont use. This is the only i7 feature that shows real performance gains. In heavily optimised multithreaded encoding/number crunching type apps, hyperthreading can be worth up to 25% performance gain. It's usually much less gain, and is 0 gain in games. Due to the way games are coded they are never likely to see that full 25% gain from hyperthreading, even if they are optimised to make use of it. Even if they do, that's 25% performance increase for a 50-60% CPU price increase, plus a more expensive mobo.

IMHO i7 just aint worth it unless you're using those apps that actually benefit from hyperthreading, and your time is money. Otherwise i5 is a much better bang for buck choice, which is why I got one :)

Oh yeah - with X58 there is the six-core i7 as a potential upgrade. But the reality is the 980 will remain ridiculously priced until it disappears. By the time six-cores is needed in gaming and people's i7 quads are struggling, there will be mainstream six and probably eight-cores available cheaper than and outperforming i7 980. So imho forget that as an upgrade path and good reason to go X58.
Click to expand...

Thanks for clearing the whole thing up! Looks like (if I can't hang on til SandyB) i'll be getting an i5.
 
No - i5 needs a P55/H55/H57 socket 1156 mobo. Only an i7 will run on an X58 socket 1356 mobo.
 
Last edited:
Liampope said:
snip
Click to expand...

Here's one for you then.

In a money-means-next-to-nothing world, for the ideal Single GPU gaming solution, a s1156 i5 is better than a s1366 i7. However, what about a s1156 i7 such as the 860 or 870. These chips are often overlooked and completely discarded. When money is an issue, they're usually around £50 dearer than the i5 range, so are they worth it? Even at stock speeds any comparison benchmark between the two shows the 860/870 storming ahead of the 750/760 in synthetic tests like rendering, coding and decoding, compressing etc. And also at stock speeds, considering the i5 does have an amazing turbo boost, the i7 still comes top over the i5 in half the scenarios.

Thoughts? :D
 
bJN said:
Here's one for you then.

In a money-means-next-to-nothing world, for the ideal Single GPU gaming solution, a s1156 i5 is better than a s1366 i7. However, what about a s1156 i7 such as the 860 or 870. These chips are often overlooked and completely discarded. When money is an issue, they're usually around £50 dearer than the i5 range, so are they worth it? Even at stock speeds any comparison benchmark between the two shows the 860/870 storming ahead of the 750/760 in synthetic tests like rendering, coding and decoding, compressing etc. And also at stock speeds, considering the i5 does have an amazing turbo boost, the i7 still comes top over the i5 in half the scenarios.

Thoughts? :D
Click to expand...

The s1156 i7s are basically quad-core s1366s- they have the hyperthreading bonus that the i7 has with it, but also they come with the turbo boost of the i7, which is lacklustre when compared with the i5 (of course, this point is moot when overclocking).

Hyperthreading and extra cores work wonders for rendering, coding/decoding, and all that other lovely CPU-intensive work. For gaming, hyperthreading means nothing. A core count above 3 means next-to-nothing, and for almost all games, all you need is 2, so the Turbo Boost really comes into play (again, if you're not overclocking).

For these reasons, the i7 8xx is actually worse (or the same, assuming equal clock speeds and no turbo) for gaming than the i5 760, which is why I'd recommend the i5.

If you've really got money to burn, the i7 9XX series may offer small improvements because it clocks well- and the extra PCIe x16 lane works really well with SLI/xfire- but I'd sooner spend it on a bigger, flashier graphics card.
 
i7 8xx = i5 7xx with hyperthreading - the only i7 feature worth having. So ticks a lot of boxes really. But it's the same price as an equivalent i7 9xx, so you can understand people building a new system looking to get an i7 opting for X58/1356 instead. Mostly makes sense for someone doing number crunching or something else that will benefit from hyperthreading, but who still wants to save a fair chunk on the mobo. If my usage ever changes from pretty much mostly gaming to anything that benefits from hyperthreading, or games begin to show a gain, I might pick up a second hand i7 8xx and slot it in, but it would have to cost not much at all for the swap as it really wouldn't be a big performance gain.
 
You must log in or register to reply here.
Back
Top Bottom