Overclock.net banner

1 - 9 of 9 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter · #1 ·
I built my pc in December 2018 and still lack much of the necessary knowledge required to say "I built a PC" in public. Specs:
CPU: i3-8100 @ 3.6 GHz (9th gen?)
GPU: Zotac Mini GTX 1050 Ti
Board: MSI Z370 PC Pro
RAM: Patriot Viper DDR4 2 x 8GB
PSU: EVGA 450 BT Bronze
Storage: Crucial MX500 500GB and another old 500GB HDD


I'm planning on upgrading to an i5-9400F @ 2.9 GHz and using the included fan cooler. Those of you who know how/where to do these calculations, what's the maximum frequency to which I can boost it without causing issues?
If you could link an easy guide to how to boost the frequency, that would be great as well but don't stress.
 

·
Registered
Joined
·
129 Posts
Hi, your current CPU i3-8100 is 8th gen Intel.

The i5-9400F CPU you are planning on upgrading to is 9th gen and is not over clockable as it is not the "K" or "KF" version.

The only way to over clock that CPU is to over clock the BCLK (front side bus clock of the CPU) which is very finicky and can cause all kinds of other stability issues with the system.

This all depends of course that your mother board is a Z series chip set and has the ability\setting to over clock the CPU.
 
  • Rep+
Reactions: The Pook

·
9 Cans of Ravioli
Joined
·
21,422 Posts
like jonkrmr said, you bought the wrong CPU if you wanna OC.

The only way to over clock that CPU is to over clock the BCLK (front side bus clock of the CPU) which is very finicky and can cause all kinds of other stability issues with the system.

This all depends of course that your mother board is a Z series chip set and has the ability\setting to over clock the CPU.
OCing via BCLK doesn't cause instability since BCLK was decoupled from PCIE and SATA via an external clock gen (which happened on Skylake, it's why OCing locked Skylake CPUs was a thing and didn't cause problems).

the problem with raising BLCK nowadays is that IME won't let non-K SKUs boot above ~103 on anything since Kaby Lake, so it's basically useless on anything but a K-SKU.

My Z390 Taichi will boot my 9900K at >300 BCLK and would be rock stable, but when that board got moved to NAS duty and it got paired with a locked SKU it won't boot much above ~3%.
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #4 ·
the problem with raising BLCK nowadays is that IME won't let non-K SKUs boot above ~103 on anything since Kaby Lake, so it's basically useless on anything but a K-SKU.

My Z390 Taichi will boot my 9900K at >300 BCLK and would be rock stable, but when that board got moved to NAS duty and it got paired with a locked SKU it won't boot much above ~3%.
Not to discredit anything that you're saying, but I would like multiple opinions on this.
In this video that I found, he changes the BCLK frequency only by ~3% and instead increases the All Core frequency under CPU Ratio. Would this work as opposed to increasing the BCLK frequency?
 

·
Registered
Joined
·
999 Posts
Not to discredit anything
@The Pook has 21,000+ posts on this forum. I think he knows a thing or two about Intel processors.

You need a K series CPU to do some All Core overclocking. The video you posted does not show CPU-Z when the CPU is fully loaded running Cinebench. That is usually a sign that someone is trying to hide something.
 

·
9 Cans of Ravioli
Joined
·
21,422 Posts
Not to discredit anything that you're saying, but I would like multiple opinions on this.
In this video that I found, he changes the BCLK frequency only by ~3% and instead increases the All Core frequency under CPU Ratio. Would this work as opposed to increasing the BCLK frequency?
that's Haswell, and Haswell wasn't limited by IME. IME didn't limit base clock until after Skylake because people were base clock overclocking locked CPUs.

the issue with overclocking locked SKUs pre-Skylake (ala, Haswell) was that most boards didn't have an external clock gen (I don't know of any that did). BCLK was linked to other things, with the major issues being PCIe and SATA. If you pushed the base clock too high, then you'd either get PCIe slots that stopped working, drives that stopped getting detected, or you'd corrupt data.

Regardless, the video you posted was for Haswell, not Coffee Lake. The thing you have to worry about is IME. If you have a Z series board you can enable MCE but that's the closest you're going to get to overclocking (aside from raising BCLK ~3%).

@The Pook has 21,000+ posts on this forum. I think he knows a thing or two about Intel processors.
that's not really fair, I don't know more than I know :)
 

·
Registered
Joined
·
129 Posts
like jonkrmr said, you bought the wrong CPU if you wanna OC.



OCing via BCLK doesn't cause instability since BCLK was decoupled from PCIE and SATA via an external clock gen (which happened on Skylake, it's why OCing locked Skylake CPUs was a thing and didn't cause problems).

the problem with raising BLCK nowadays is that IME won't let non-K SKUs boot above ~103 on anything since Kaby Lake, so it's basically useless on anything but a K-SKU.

My Z390 Taichi will boot my 9900K at >300 BCLK and would be rock stable, but when that board got moved to NAS duty and it got paired with a locked SKU it won't boot much above ~3%.
@The Pook, I stand corrected.

I bow to the master :)
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #8 ·
Regardless, the video you posted was for Haswell, not Coffee Lake. The thing you have to worry about is IME. If you have a Z series board you can enable MCE but that's the closest you're going to get to overclocking (aside from raising BCLK ~3%).
I hate to be this guy, so this is my last question.
the i5-9400F is advertised as being able to turbo to 4.1 GHz. As it wouldn't say that if it wasn't possible, how would I go about increasing the clockspeed to that point?
 

·
9 Cans of Ravioli
Joined
·
21,422 Posts
I hate to be this guy, so this is my last question.
the i5-9400F is advertised as being able to turbo to 4.1 GHz. As it wouldn't say that if it wasn't possible, how would I go about increasing the clockspeed to that point?
it'll turbo one core to 4.1 out of the box without you needing to set anything, but you'll only see it when you're basically idle at the desktop for a few milliseconds at a time. it's just a marketing number.

2488426



even if you run a program or a game that is only single-threaded, you won't see cores boost to 4.1 since Windows and background processes means you're putting load on >1 core.

if you have the option to enable MCE in the BIOS then it'll set the single core turbo speed to the all core turbo speed, but setting a 4.1 CPU to run at 4.1 isn't overclocking.
 
1 - 9 of 9 Posts
Top