Overclocking is not an exact science, each chip will have it's individual limits which is why PCS will say "minimum of". So it could be anywhere from that upwards.So gonna be going for a 9900K with a H100i Platinum Pro RGB.
I was wondering how much PCS OC? And if a H100i would suffice for how much they OC. Are we talking a moderate overclock they do or a serious one?
which is why PCS will say "minimum of".
CaseOverclocking is not an exact science, each chip will have it's individual limits which is why PCS will say "minimum of". So it could be anywhere from that upwards.
It's usually a relatively modest overclock, nothing extreme.
If you post your proposed build, say what it's for and what monitor you're pairing it with, plus what your max budget is, we can advise further.
Thank you alot man. Really gave me some insight. Will probably get the K and let turbo do its stuff. £60 extra is a little steep for what you get i think. CheersSlighly long post but if you're buying a £500 CPU, 20-25% of the total price of your PC, you should probably know what you're buying:
Nearly all desktop CPUs have turbo boost, and it's turned on by default.
Turbo boost on Intel CPUs boosts the cores above the "base clock" (3.6GHz in the case of the 9900k) upto a certain value. That value is even higher if the CPU is under load on only a single or a few cores.
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Side note: in theory, Turbo Boost only has a limited duration for the max frequencies, after which in order to stay within certain power limits, the frequencies would drop again - still higher than base clock, but not as high as the max. However, in practice many motherboards ignore those limits and just let the CPUs run at their full boost frequencies indefinitely.
So as you can see, left it its own devices without any overclock, the 9900k would boost itself upto 5GHz if only 1 or 2 cores are loaded. If 5-8 cores are loaded up, it's 4.7GHz.
What the -K CPUs have that the ones without a K don't, is an unlocked multiplier. The multiplier is how many times the "BCLK" the CPU runs. The BCLK is always 100MHz. So if a CPU is clocked at 4GHz, it would have a multiplier of 40, for example. The BCLK governs not only the CPU, but the RAM, and even the PCIe - so it is usually left alone at its default 100MHz.
You generally overclock Intel CPUs by increasing the multiplier to a given value (usually over the turbo boost frequency) and then feed it enough extra voltage so it's stable running at that faster speed. An unlocked multiplier means you can change the multiplier value (i.e. you can overclock it). The i9 9900 (without the k) has a locked multiplier, which means you can't change the value i.e. you can't overclock it. The i9 9900 is - separately to the multiplier issue - 1-200MHz slower than the 9900k. Just to make it a bit cheaper and give you another reason to want to buy the 9900k instead of the 9900.
What PCS apparently do is set the multiplier at upto 49, so the CPU runs upto 4.9GHz. If this is how they do it, it means the CPU wouldn't hit its 5GHz max potential available under normal turbo boost. And will therefore run slower with the overclock than without it, in some situations. Perhaps games like Far Cry.
The i9 9900ks boosts itself to 5GHz on all 8 cores. And so is faster than the 9900k's all-core turbo boost by 300MHz. And is also faster than the 9900k overclocked by PC Specialist by 100MHz on all cores. Or perhaps more - PCS only say upto 4.9GHz, they don't guarantee it. They might set it to 4.85GHz or even 4.8GHz, potentially.
You have a lot of options.
Buy a 9900k without the overclock and leave it alone. Let Turbo Boost do its thing.
Buy a 9900k without the overclock, and overclock it yourself to 5GHz.
Buy the 9900KS which already boosts to 5GHz without an overclock (and optionally try OCing it yourself).
The one option I would rule out altogether is buying a 9900k pre-overclocked by PCS. For the reasons above.