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by prodmerc 3329 days ago
Meanwhile I'm trying to find a way to remove the hard lock on CPU and RAM frequencies (extreme CPUs can't be overclocked, RAM is locked at 1333 MHz) :)

Looks like it can be done through Management Engine, which has access to everything apparently.

Only success so far is unlocking BCLK, but the overclock is small and unstable that way.

Another roadblock was the read only lock, which can fortunately be bypassed on POST on xx67/77 chipsets.

3 comments

> extreme CPUs can't be overclocked

You mean non-extreme?

> unlocking BCLK, but the overclock is small and unstable that way

On desktop Skylake, BCLK can get you to anywhere you want (I run an i5-6400 at 4.5GHz daily, over 4.7 for benchmarks). You're talking about laptops, right?

Laptop, and extreme CPU. HP and Dell block TPL/TRL adjustment even for XM processors, and HP took it even further with their 1333 MHz limit on RAM. I have 1600 MHz sticks that can run fine at 1866 and probably more (tried with Thaiphoon Burner), so that's really annoying. I don't want an Alienware to get that.

And BCLK allows for a 5MHz overclock, which is not much, anything more and the system crashes. Which is really strange, may have something to do with PCIE as Dogma said.

I just want to get everything out of my extreme processor and RAM.

Isn't that a bad idea... laptops have significant thermal limitations, things start going wrong quickly when you push beyond those. I've not done any serious overclocking but most seem to stick to desktop and buy more capable cooling systems to make it sustainable.
Aside from heatsink limitations (which can be modded to achieve better cooling), people are pushing their gaming laptops to 80W and beyond, with overclocked GPUs as well.

Some are resorting to dual PSU's to handle the power requirements, so the system boards are capable of handling some insane load.

I myself squeezed another year out of a Core 2 Quad laptop by overclocking everything as much as possible. Temperatures were averaging 90-95 under load, but I didn't care at that point, as I was going to upgrade. It still works :D

BCLK overclocking is heavily motherboard dependent, you need a very good external clock reference and in any case once you go over 3-5mhz you drop your PCIE rates from 3.0 to 2.0.

Intel's HEDT platform supports proper CPU strap overclocking withou adverse effects, but even then it's usually not recommended unless you are doing extreme OC and that's liquid nitro :)

> On desktop Skylake, BCLK can get you to anywhere you want

I thought Intel shut this down with microcode updates.

Microcode can't know anything if all power management is completely disabled :P You need a special firmware build for that: http://overclocking.guide/intel-skylake-non-k-overclocking-b...
e_context? but good luck anyway.
Try SetFSB.