Question about PCS OC

AlexJames

Bronze Level Poster
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?
 

SpyderTracks

We love you Ukraine
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?
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.

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.
 

Oussebon

Multiverse Poster
which is why PCS will say "minimum of".

PCS actually specify a maximum of - it's "upto X GHz"

And the maximum they give for the 9900k is 4.9GHz which is actually below the 5GHz single core boost frequency of that CPU.

Furthermore, PCS's overclocked systems used to be ~£10 more than a stock system. These days they are £40 or so more.

If you want an overclocked 9900k, buy the 9900ks, which comes with its own 5 GHz all core boost at stock speeds anyway. And optionally OC that a bit yourself.
 

AlexJames

Bronze Level Poster
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.

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.
Case
NZXT H500 MID-TOWER GAMING CASE (WHITE)
Overclocked CPU
Overclocked Intel® Core™ i9-9900K Eight Core (3.60GHz @ up to 4.9GHz)
Motherboard
Gigabyte Z390 AORUS PRO: ATX, LG1151, USB 3.1, SATA 6GBs - RGB Ready
Memory (RAM)
32GB Corsair VENGEANCE RGB PRO DDR4 3200MHz (2 x 16GB)
Graphics Card
8GB NVIDIA GEFORCE RTX 2080 SUPER - HDMI, 3x DP GeForce - RTX VR Ready!
1st Storage Drive
1TB Samsung 860 QVO 2.5" SSD, SATA 6Gb/s (upto 550MB/sR | 520MB/sW)
2nd Storage Drive
2TB SEAGATE BARRACUDA SATA-III 3.5" HDD, 6GB/s, 7200RPM, 256MB CACHE
DVD/BLU-RAY Drive
NOT REQUIRED
Power Supply
CORSAIR 750W TXm SERIES™ SEMI-MODULAR 80 PLUS® GOLD, ULTRA QUIET
Power Cable
1 x 1 Metre UK Power Cable (Kettle Lead)
Processor Cooling
Corsair H115i RGB PLATINUM Hydro Series High Performance CPU Cooler
Thermal Paste
STANDARD THERMAL PASTE FOR SUFFICIENT COOLING
Sound Card
ONBOARD 6 CHANNEL (5.1) HIGH DEF AUDIO (AS STANDARD)
Wireless/Wired Networking
WIRELESS 802.11N 300Mbps/2.4GHz PCI-E CARD
USB/Thunderbolt Options
MIN. 2 x USB 3.0 & 2 x USB 2.0 PORTS @ BACK PANEL + MIN. 2 FRONT PORTS
Operating System
Windows 10 Home 64 Bit - inc. Single Licence [KUK-00001]
Operating System Language
United Kingdom - English Language
Windows Recovery Media
Windows 10 Multi-Language Recovery Image - Unlimited Downloads from Online Account
Office Software
FREE 30 Day Trial of Microsoft® Office® 365 (Operating System Required)
Anti-Virus
BullGuard™ Internet Security - Free 90 Day License inc. Gamer Mode
Browser
Microsoft® Edge (Windows 10 Only)
Warranty
3 Year Standard Warranty (1 Month Collect & Return, 1 Year Parts, 3 Year Labour)
Delivery
STANDARD INSURED DELIVERY TO UK MAINLAND (MON-FRI)
Build Time
Standard Build - Approximately 7 to 9 working days

This is my build. 2,224 for an OC and 2,213 for a non OC.
1440P Gaming and 1440 144HZ Monitor. Will be needing 32GB Ram for a mix of gaming and work.
 
Last edited:

Oussebon

Multiverse Poster
If you're happy, or a -K and OC it yourself to 5GHz all core, which unless you're rather unlucky should be achievable.
 

Oussebon

Multiverse Poster
Slighly 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.

1573947536212.png


1573947554318.png



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.
 
Last edited:

AlexJames

Bronze Level Poster
Slighly 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.

View attachment 14405

View attachment 14406


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.
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. Cheers
 
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