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Fishy
22-08-2006, 08:13 PM
Well i'm building a computer (read signature) and I just noticed most new games say it's recommended to have a 2.4Ghz CPU to play it.
As my signature says I am planning on buying an AMD Athlon 64 X2 Dual Core 3800+ which is clocked at 2Ghz. Before that i was planning on buying an AMD Athlon 64 3500+ which is funnily enough $107 cheaper but clocked at 2.2Ghz. So its cheaper, but HIGHER clock speed. HUH?

So, what i'm wondering about here is should i get the dual core 3800+ or the 3500+?

OR go and get an Intel Pentium D Dual Core 915 which is $12 cheaper than the dual core 3800+ but clocked at 2.8Ghz and has a whopping 4mb L2 cache compared to the 1mb AMD's.

Also i'm not planning on overclocking anything because that's to complicated, and i don't want to overheat anything, i'm keeping it simple

Thanks for any help in advance :D

godfather
22-08-2006, 08:22 PM
The AMD "ratings" 3800+, 3500+ etc are "relative" or "effective" clock speeds in comparison to the Intel CPU's, as they use an entirely different architecture so raw clock speeds cannot be directly compared.

The games refer to effective clock speeds not raw ones.

Pete O'Neil
22-08-2006, 08:28 PM
It all comes down to effeciency per clock cycle, which is generally related to the length of the pipeline. Architectures with longer pipelines benefit from greater levels of cache. The Athlon64 processors have a 12 stage pipeline compared to the P4's which have a 31 stage pipeline. Longer pipelines allow for higher clockspeeds, but are less effecient, whereas shorter pipelines are more effecient but cant clock as high. This is why in alot of cases the 3800+ outperforms a 3.6GHz P4. The new Intel Core2 Duo's have shorter pipeline like the Athlon64.

The_End_Of_Reality
22-08-2006, 08:30 PM
What they say is 2.4GHz Pentium or equivelant, AMD CPUs do more data per cylce than Intel, which means lower clock speeds, but higher performance, AMD is the CPU for gaming over Intel Except for Conroe, but that is expensive.

Yes, the higher clock speed might be cheaper, but what does DUAL CORE mean? it means there are 2 CPUs instead of one, this will give theortically twice performance, but realisticlly it is about 80% increase and it IS worth it.

The Pentium 915 has 2Mb cache per core, yes you are right the X2 3800+ only has 1Mb per core, but look at this (http://reviews.cnet.com/4520-10442_7-6389077-1.html) (it does not have the 9XX series though) but you will get the general idea

Fishy
22-08-2006, 09:47 PM
The AMD "ratings" 3800+, 3500+ etc are "relative" or "effective" clock speeds in comparison to the Intel CPU's, as they use an entirely different architecture so raw clock speeds cannot be directly compared.

The games refer to effective clock speeds not raw ones.

Ohhhhhhhhhhhhhhhh so you can't compare them, that's exactly what i was doing so no wonder i was going *** why is intel so much higher?!


It all comes down to effeciency per clock cycle, which is generally related to the length of the pipeline. Longer pipelines allow for higher clockspeeds, but are less effecient, whereas shorter pipelines are more effecient but cant clock as high. This is why in alot of cases the 3800+ outperforms a 3.6GHz P4. The new Intel Core2 Duo's have shorter pipeline like the Athlon64.

Oh ok so clock speed isn't everything! Thanks, i'm starting to understand a bit better now.



Yes, the higher clock speed might be cheaper, but what does DUAL CORE mean? it means there are 2 CPUs instead of one, this will give theortically twice performance, but realisticlly it is about 80% increase and it IS worth it.

The Pentium 915 has 2Mb cache per core, yes you are right the X2 3800+ only has 1Mb per core, but look at this (http://reviews.cnet.com/4520-10442_7-6389077-1.html)

I thought dual core just meant it had 1 extra part of the CPU, not another one slapped on. Thanks for the link, very helpfull.