Quad Core vs Dual Core and Core i7 vs Core 2

[Guest]

Hi,
I'm a programmer who would like to play some games again and I'm just looking for some advice on hardware.
Topical games for me are "Mirror's Edge", "Dead Space" and "Crysis".

I have pretty much settled on the GTX295 but I'm not as certain on the CPU; dual core, quad core, Core 2 or Core i7? First, I've looked at the E8400, my main concern is if this CPU will create a bottleneck for any of these games (note: coupled with GTX295), or not. Assuming the latter to be true, i.e. that the GTX295 is the bottleneck with an E8400 -- then there obviously isn't any point in buying a more expensive CPU, in the context of gaming.
I've read several reviews of e.g. Mirror's Edge, but when the reviews test with the most high-end graphics cards they tend to use the most extreme CPUs also. So even though Mirror's Edge runs at > 100 FPS on the test system at the review site, it might not do so on a system with a weaker CPU, and it is tricky to find reviews that take this into account -- at least I haven't found any.

1) Will an E8400 be a bottleneck when coupled with the GTX295 for these specific games?
2) Assuming 1) is true, will these specific games benefit from a quad core?

If anyone has some actual frame rates or source(s) that have such frame rates then that would be great.

It is also difficult to find actual verifiable sources on how many threads Unreal Engine 3 and Cryengine 2 utilizes -- even if some source states the engine can scale to n cores it doesn't necessarily state if core 3 and 4 is utilized anything more than a few percent, which makes it pretty trivial and pointless!
But technical issues aside I'm basically wondering about the real world issues for these specific games with this specific hardware dilemma. Any thoughts?

Thanks in advance!

 

[festerovic]

I think the direction of your logic is interesting, considering that the price difference between systems using the chips you mention. Compare the money saved from a dual core system with the excellent performance and future proofing you will see from an i7 system, and your question becomes a lot easier to answer.

 

[flyin15sec]

Go ahead and read fully this review of CPU scaling with GTX295. It'll answer most of your questions.

http://www.legionhardware.com/document.php?id=807

As it is, an E8400 could power a GTX295 fine. It boils down to what else you plan on doing, and what type of upgrade plan you are or aren't planning.

 

[Helloworld_98]

TBH anyone buying a dual core nowadays either buys a new best-price-for-gaming-performance PC every 6 months or they don't have the money to buy a Quad core.

Also since more and more games can use 4 threads then go for a Quad core, and if you get an i7 cpu it will last even longer because it can handle 8 threads at a time.

 

[Guest]

I see your point, festerovic, but this really is a stochastic problem as I don't even know how long I will keep gaming -- as my gaming habits are not exactly predictable.
There is a huge price difference between the cheap Core 2 duo and the expensive Core i7 quad core, as you mentioned; but as a long term investment it may, or may not be profitable -- and if it perhaps gives a reasonable performance boost as of today to have such a CPU system, then it might be the better choice?

The link posted by flyin15sec was useful. Thanks. Unreal Tournament 3 uses the (obviously) Unreal Engine 3 -- which is the same as the engine utilized in Mirror's Edge and I will then dare use that as a basis for this conjecture regarding Mirror's Edge, and assume that there are no noteworthy differences between Crysis and Crysis Warhead as they both use CryEngine 2 in the context of performance regarding different processor types, I'm aware Crysis is more demanding than Crysis Warhead.
When utilizing Unreal Engine 3 there seems to be ~15% difference from 2 cores to 4 cores and a ~9% difference from Core 2 quad to Core i7 quad. [1]
As for CryEngine 2 there is no difference from 2 cores to 4 cores, but again ~9% difference from Core 2 quad (and duo in this case) to Core i7 quad. [1]

The difference seems to decline in proportion to screen resolution in both cases. [1]

Due to the fact there is such a small real world improvement in Core i7 over the former revision of the Core architecture I will favor the Core 2 solution. Given a Core i7 system the idea is obviously that I might buy a new graphics card in a few years as well as a new CPU that can power this new graphics card -- which wouldn't work as the socket 775 is assumed to be not available at that time.
However, it would entail in total a purchase of: CPU, graphics card and PSU; i.e. I don't have to buy the motherboard and (DDR3) RAM. Since DDR2 RAM is cheap (extremely so, actually so much I'm shocked, to me 16 MiB still sounds like a lot) and I will not buy a very expensive socket 775 motherboard I don't see it as saving a whole lot on the investment in a socket 1366 system at this time.

To buy a socket 1366 system at this time costs a lot more than a cheap socket 775 system and they both perform very similar in many cases; saving the price of a socket 775 motherboard and 4 GiB DDR2 RAM doesn't seem to be worth it to me.


[1] http://www.legionhardware.com/document.php?id=807

 

[Guest]

TBH anyone buying a dual core nowadays either buys a new best-price-for-gaming-performance PC every 6 months or they don't have the money to buy a Quad core.

Also since more and more games can use 4 threads then go for a Quad core, and if you get an i7 cpu it will last even longer because it can handle 8 threads at a time.

Keep in mind that SMT only entails a small gain in real world performance where empty holes on the pipeline can be filled with ops from arbitrary threads. It is merely a perverse way of using an enormous chunk of transistors to gain a (relatively) very small real world performance gain -- although, it is still very neat, obviously.

As for more and more games that utilize 4 threads, how true is this? Are there any games as of present time that have a major difference in performance when moving from two to four cores? If so, then that implies the graphics card is not the bottleneck anymore, which it still seems to be?

 

[Bluescreendeath]

The only game I can think of that actually uses more than 2 cores is perhaps
"Lost Planet"

Even CPU intensive RTS's like Supreme Commander doesn't use more than 2 cores, and system-killer games such as Crysis doesn't use more than 2 cores either.

Most games (99%) out there either use only 1 or 2 cores.

 

[gimpy1]

posixmemalign,

I agree with you. I use a 8400, and I am happy with it. These chips are great overclockers, and once you are up in the 3.8 Ghz+ range, you can play anything you want (assuming you have the GPU).

As far as the difference in CPU limited games like Unreal, who cares. As most monitors refresh at 60 Hz, what does it matter if you are only getting 126 fps as opposed to 136.

Good luck with your build.

 

[The_African]

This is just a thought, coming from a non-gamer

This is also slightly off topic but may help you descide, posixmemalig.

If current games can only handle 2 cores and you have a quad core system.
Would it be possible to tell the game, maybe using task manager in windows, to run on cores 3 and 4. While the everything else like windows and utilities run on 1 and 2? Surely there would be some potential there for more power of having 2 cores just for the game?

 

[Bluescreendeath]

This is just a thought, coming from a non-gamer

This is also slightly off topic but may help you descide, posixmemalig.

If current games can only handle 2 cores and you have a quad core system.
Would it be possible to tell the game, maybe using task manager in windows, to run on cores 3 and 4. While the everything else like windows and utilities run on 1 and 2? Surely there would be some potential there for more power of having 2 cores just for the game?

Nope. Telling the other cores to do stuff is the work of software developers...and they're too slow/lazy to do it. (took us 5 years just to get to software using 2 cores)

 

[Guest]

This is just a thought, coming from a non-gamer

This is also slightly off topic but may help you descide, posixmemalig.

If current games can only handle 2 cores and you have a quad core system.
Would it be possible to tell the game, maybe using task manager in windows, to run on cores 3 and 4. While the everything else like windows and utilities run on 1 and 2? Surely there would be some potential there for more power of having 2 cores just for the game?

What you're referring to is called setting the affinity for a specific process, and yes, this is possible in the Windows NT family.

However, you seem to be unaware of the fact that the OS already has what is called a scheduler which through a clever algorithm decides not only how much process time any given process should get but also on what processor said process/thread should execute. Windows NT uses a multilevel feedback queue in its scheduler. [1]
There are many books on this subject and it is much more advanced than possible to give any justice in a post on a forum, suffice to say, what you're describing is already handled by the OS entirely -- if the game in question uses 100% of CPU 1 and CPU 2 and some arbitrary background process needs to perform CPU intensive work, the scheduler will elect the CPU with the least load available from the n number of total CPUs; if n is 4, and CPU number three and four are basically just running the idle loop then these processors will obviously be elected for additional workload.

The OS is more intelligent than you might at first think, even though it is really stupid in the context of humans.


[1] http://technet.microsoft.com/en-us/magazine/cc162494.aspx

 

[BrianCronen]

This is just a thought, coming from a non-gamer

This is also slightly off topic but may help you descide, posixmemalig.

If current games can only handle 2 cores and you have a quad core system.
Would it be possible to tell the game, maybe using task manager in windows, to run on cores 3 and 4. While the everything else like windows and utilities run on 1 and 2? Surely there would be some potential there for more power of having 2 cores just for the game?

You can, in Task Manager, you can Right Click> Set Affinity > Unclick Core 0 and Core 1, Click Core 2 and Core 3. Then, the program will be forced to only utilized Core 2 and Core 3. However, every time a program restarts, you'd have to reapply those settings, and it is really such a hassle. Mainly, the hassle is that most of your Windows background programs and services have affinity set to all 4 cores, so to do this, you have to disable every background service and program on Cores 2 and 3.

As for the original poster, I am sure an E8xxx would be lovely for gaming, a Q9xxx would be pretty nice too, and if the GTX was indeed bottlenecked by the CPU, you could always un-bottleneck it with a rather modest overclock. On a price point, since you aren't sure how long you will be gaming, I'd say a decent, mid-range CPU with a modest (read: small, just to give it headroom against the GTX, and provide some comfort knowing it isn't bottlenecked) overclock would be enough to do the job. And as someone above said, you can get a more updated socket if you wish, to make your mainboard last longer with future products.

 

[hefox]

Here is an good example of a game that knows more than 2 cores and as you can see it's a big deference between E8500 and i7 920/Q9770 not to mention 3 SLI.
http://www.guru3d.com/article/intel-core-i7-920-and-965-review/18
I have many examples like this when games know more than 2 cores. as you can see in the link below, Tomshardware did a review about this.
http://www.tomshardware.co.uk/multi-core-cpu,review-31567-10.html