A few things here:
When AMD name their CPU's they are always rate them against the Intel equivelent not there own range, quote:
"The performance for the Athlon64 3500 is equivalent to the performance of an Athlon Thunderbird running at 3.5GHz"
"The Thunderbird core" was the original socket A Athlon that only went up to 1.4Ghz so the analogy just doesn't work (I accept that P4 was also mentioned)
Basically Athlon64's speed ratings are compared directly to P4's true clock speeds at around the same performance.
Also AMD's budget Sempron's are rated as compared to the equivelent budget Intel Celeron's true clock speed again more or less the same performance.
As for fans.
Well I note you are looking at a fairly high end setup, performance generally means heat, heat that needs to be taken out the case efficiently, that brings us back to fans and the need to have a reasonable turn over of air internally so as not to allow temperatures to rise too much.
The CPU is the number 1 heat generator followed by the graphics card and then the hard drive. The CPU and normally the graphics card have their own fans but as these fans are air coolers their efficiency is directly related to the temperature of the air they are using to cool the component.
Thats why case cooling is so important, by tuning over the air in the case all internal components will effectively be running at lower temperatures and this as you can appreciate will help reliability and the longevity of your parts.
The usual basic setup is:
One case fan front lower mounting point drawing IN cool air
PLUS
One case fan top rear (underneath the PSU) EXHAUSTING OUT
This is considerd standard cooling for any middle to high spec machine (note* hot air naturally rises) so this setup just helps natural convection.
Use the biggest fans that your mounting points will support.
Bigger fans are normally quieter for any given CFM rating (less noise/higher volume of air moved)
Ideally 120mm fans if supported.
Martin
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