CPU preformance

[077tommy]

Hi Guys,

I am slightly confused about how cpu performance works - how can a cpu that has a higher clock speed be outperformed by a cpu with a lower clock speed:

For example in lots of games the i5 3570k out preforms the fx-8350 even though the 8350 is clocked higher

Any help is appreciated !!!

[MSI_PC_GAMER]

easy cuz the 3570k is a beast :)

[Rhotis]

architecture of the chip inside. Its the same reason you can have an inline 4 cylinder outperform a V8 if you put a stock V8 against one of those inline 4s that they run in Indy racing. They are both motors but they have completely different architecture to enable them to do various things.

[znyggisen]

Obviously more factors than this, drivers, optimization etc but usualy newer (better CPUs) will have a higher IPC (Instructions per clock cycle) than predesesors. So in the case with the 8350 vs 3570k, if the IPC is higher for the 3570k than at the same clock speed, the 3570k should be faster.

[fredtechcheck]

The architecture of the CPU and the pure processing power of the CPU is really what effects how the CPU performs. Also the chipset can effect the performance of the CPU to a certain extent. The processors over cores can be a big thing like the AMD 8 core processors. The cores on the FX-8350 does not have true cores so their is not 8 physical cores. So in general the processing power of the CPU matters the most.

[znyggisen]

The architecture of the CPU and the pure processing power of the CPU is really what effects how the CPU performs. Also the chipset can effect the performance of the CPU to a certain extent. The processors over cores can be a big thing like the AMD 8 core processors. The cores on the FX-8350 does not have true cores so their is not 8 physical cores. So in general the processing power of the CPU matters the most.

Actually it has 8 physical cores but resourses are shared between them. AMD calls them moduels and have physical components to them even though it's not a 100% duplicet, but it's still slightly different than Intels hyperthreading in that there is actualy physical componentry that makes up all "8 cores".

[Swifty]

The way instruction sets have been implemented into the CPU. Not only that, but the way the CPUs are built. Higher speed doesn't mean more information is processed compared to multiple cores clocked slightly lower, as was the performance increase seen from Pent 4 to Core.

And as above; the AMD chips aren't 100% full cores. They're about 75-85% of a core per core. Intel's aren't true oct cores either, but they have Hyper threading, which feeds two threads in to the CPU, allowing for better handling of current tasks.

However, the AMD chips are still pretty beastly. Just because they appear to not perform too well at the moment, or at launch, doesn't take away that they're amazing performance for value.

[xAcid9]

The FX-8320 is a much better value in my opinion.

A lot of games is not optimized for multi-cores CPU. Intel proc have better single core performance, that's why you'll see the i5 beat the FX in many games.

[christoi]

Just to expand upon the underlying architecture of the FX, each "module" consists of two cores, which shares certain resources. This means that the chip itself is very like a normal 8-core and you can make use of the thread-level parallelism. The problem however, is the performance slows when you do tasks that require those resources. As a result, overall IPC suffers when using two cores in the same module, though it's designed so that the difference isn't too large.

For the purposes of understanding how they differ performance-wise however, that's really not important in my opinion. It's just one reason why the IPC of Vishera is lower when compared to Ivybridge.

[077tommy]

Thanks for the quick responses - right now I have a fx-4100 clocked at 4.5 ghz - is it worth upgrading to the fx8350 - will I see any major improvement in games ???

(I have a club 3d 7870 (should be called a 7890) amd 8gb of corsair vengeance ram)

[christoi]

Thanks for the quick responses - right now I have a fx-4100 clocked at 4.5 ghz - is it worth upgrading to the fx8350 - will I see any major improvement in games ???

(I have a club 3d 7870 (should be called a 7890) amd 8gb of corsair vengeance ram)

Not really, to say the least. The performance difference with games between processors are typically very small in the first place, plus you are probably hitting a GPU-bottleneck with that kind of an overclock so the differences would be even smaller. For a gaming rig that looks to be fine for the time being, I personally wouldn't bother upgrading for at least another year.