Newbie Need Help. About Cache.

Well

I am afraid I cannot answer this question in a technical manner but I would think of it as RAM. The higher the cache, the better. Suppose an Athlon 64 has 512KB cache and runs at 2.2Ghz. It's newer brother would have 1MB cache and also run at 2.2Ghz. It should then be faster at some operations because there would be more cache available for it to take advantage of.

JAN :D
 
Yes, cache is high speed RAM that is usually(pretty much always now) located on the CPU die. The more cache you have, generally the better and faster the CPU runs but not always. Say you had a boatload of cache but what you were doing didn't use the same data again, the CPU always looks in cache first and so it's slower to always check the cache when you don't need too. Also, the more cache you have the 'slower' it gets, it still runs at the CPU clock speed (for on-die cache) but it has higher access latencies.
 
Cache also is on hard drives and dvd/cd drives. I believe cache on a DVD/CD burner works like this, when your burning files to a dvd/cd, the data goes into the cache first, then from the cache to the disc, this way there is an no interuption from the burning process.
 
If I'm not mistaken, a 2mb cache on the CPU is actually slower because of the time it takes to search the cache. I'm pretty sure a cpu with a 1mb cache and a cpu at the same clock with a 2mb cache, the 1mb cache cpu will actualy perform better.
 
The access latencies on the 2MB Prescotts is about 20% (give or take) longer, so yes at the same clock speed the 1MB Prescott will have faster cache access, this doesn't necessarily mean the performace of the 1MB is better. For gaming, only a few games make use of the extra cache (mainly doom3) otherwise the 2MB and 1MB models perform almost exactly the same. For 3D animation the 2MB cache is well worth it though. However there are features other than the cache on the 6XX series that make it worth buying.
 
because of the time it takes to search the cache
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Maybe I misunderstand here.

Cromewells's words are spot on.

Adding more and more cache past a certain level is pointless. It's the same as throwing out normal memory and replacing it all with RAM that runs at CPU clock speed.
Can be done (probably), but, pretty expensive, yes ? So cache purpose becomes redundant.

Cache is'nt searched, it's already got the data available (cache hit), or hasn't (cache miss) which forces a reload. The trick is to get the optimum trade-off between hits and misses.
Not easy !
 
Cache is'nt searched, it's already got the data available (cache hit), or hasn't (cache miss)
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Yes but one doesnt know if theres a hit or miss without searching ;)
 
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