X-bit labs Community

[cLa]

Just a quick question please, as I've never OCed and don't plan to for the moment.

Q1 :
When you overclock, you basically up the GHz, right ? But what about the cache ? Speedwise and sizewise ?

I mean, for example : compare these two CPUs :
#1, no OC, 3GHz, 4MB L2 cache
#2, OC, from x to 3GHz, 2 MB L2 cache

So, #2 has the same speed now but less cache, is it as good then ? What about the speed of the cache ?

For the sake of comparaison, let's pretend we're using two PCs that have exactly the same components except for the CPU.

It's been on my mind lately, because of course you get 3GHz for less in terms of price but isn't the performance slightly less than a "real" 3GHz ?

Q2 :
Which is easier, OCing a CPU or a GPU ?

Thank you very much.
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Thank you all very much for your patience and your help | Used to write in green

[wizard612]

I am pretty sure I am not the most qualified person on this site to post regarding your questions...but this is what I know.

Overclocking the CPU can often make up for a lack of L2 cache. Clearly if you have everything exactly the same but CPU #1 has more L2 cache it will still be better. Often times once CPU's are sufficiently OC'd the impact of the size of the L2 cache is minimal.

In regards to which is easier to OC.... I don't think there is a text book answer to that one. Personally, I feel OC the GPU is 'easier' because when you alter the GPU speed you are not altering other component speeds like you do with a CPU OC. It also depend on how far you want to OC. If you want to increase GPU voltage, GPU clock speed, and GPU memory speed that may become more complicated than a simple, mild CPU OC on stock voltages. I think the degree of difficulty in OCing a component is more dependent on how far you want to push the component opposed to what the component is.

These are very general statement and are not targeted at any particular CPU/GPU family.

If someone could confirm this is correct I think that would be most helpful.

[cLa]

Thanks for your answer, it explains it very well.
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Thank you all very much for your patience and your help | Used to write in green

[Stupify]

Let's get the simpler question out of the way first:
Q2: Both should be not that hard to OC however:
- CPU OC gives you more overall system performance
- GPU OC gives you more gaming performance
- CPU OC does not impact power usage as much as GPU OC- hence less heat generated and hence less noise (slower fan). GPU OC requires much more power and you might need to get a good fan/cooling system to ensure you GPU does not fry even for 10-20% OC. CPU's 10-20% can be done with standard fan nowadays.

Now Q1:
#2 will still be slower but not by much. The cache is what helps the CPU from avoiding the big hit taken due to FSB and/or memory latency. The impact of 2MB versus 4MB L2 cache will only be seen when the program running is more memory dependent.

The other thing about OC that would help though is that the FSB and memory might be OC too and so they work a bit faster than the non-OC. They will help but not to a point make the system faster than the 4MB CPU. #1 will win hands down in almost everything, if not all. But then the performance difference at such a level would only be negligible in most cases from an end-user perspective. The cache difference would show impact in enterprise/massive computing programs as there are more programs that are more dependent on the CPU than overall system. We, end-users joe blow, would not even notice any performance difference outside of synthetic benches.

[cLa]

Thanks !

I see now with you guys' answers, very interresting. So yeah, to all you OCers, you basically and mostly do that for gaming right ? That means you can drastically lower the price of the hardware you buy...
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Thank you all very much for your patience and your help | Used to write in green