Great !
So it looks thick!
If we make changes that may cause instability directly in the advanced options - it’s game over!
Well, unless we are a level 5 service technician with a CH341 programmer in the pocket 
…or better … changing the motherboard 
Pffff… now the Lenovo service is probably left…
But the question remains…
How to apply changes to BIOS advanced options without writing to NVRAM? Is it possible or can it be avoided?
I don’t think it can be avoided, after all any change made in the setup utility needs to be saved somewhere and there’s only so many places that can be.
Having a SPI programmer is a relief, if one does a full dump of the chip before starting the party, assuming the NVRAM data is stored there (there could still be dedicated NVRAM chips, but shouldn’t they be wiped after the CMOS battery is removed if that were the case?). Even then, from what I read, sometimes ECs connected to the flash chip that holds the firmware get angry when one tries to read/write to the flash if done directly while connected to the motherboard.
I’ve never had the pleasure of being in that situation, but I’m relatively new when it comes to dealing with flash chips in computer motherboards.
What you did yesterday to get it to POST can’t be done today right?
Really? Come on, their technicians can’t do anything other than swapping the whole board?! They ought to have access to proper tools to set things straight.
Yes, replacing the RAM will not do anything in this case, the config saved in NVRAM went up and does not let go (previously the timing was lowered compared to the original one, so replacing it with Samsung chips helped).
I’ve tried a lot of things but it doesn’t look good 
Colleague lfb6 shot this NVRAM info…
As for Lenovo, they probably misunderstood Colleague Ravenith. They want to replace the board because it’s the easiest way. They certainly have the ability to program/reset NVME in hardware.
I won’t give them the mainboard/laptop because I put liquid metal on the CPU/GPU and they better not see it 
The question is whether telling Lenovo about the real cause of the problem (digging in the advanced bios) will not lead to warranty repair…
By the way, if Lenovo had professionally approached such efficient laptops and enabled access to XMP RAM profile and OC/UV CPU settings, we wouldn’t be talking here now…
Undervolting was disabled across manufacturers because of a vulnerability that involved its use if I’m not mistaken, and OC in laptops is probably disabled because… well, more powa, more cooling needing
I was about to write that it was odd for XMP profiles not being uses, when I went up to check which memory modules you had again. Kingston Fury, 5600MT/s, as per its datasheet if it was running at 4800 & CL38 it was using an XMP profile actually JEDEC’s would have higher CAS latency ← Wrong info, I read the DIMM datasheet, not the SODIMM one.
Overclocking wasn’t enabled by default so I’m guessing that’s why the memory controller was running at its specced transfer speed of 4800MT/s and not picking up faster profiles.
Default profile (JEDEC) for Samsung 4800Mhz CL40 1.1v was originally present
Kingston as standard should work on the XMP 1 profile - according to what you attached - 5600Mhz CL40! 1.1v
In my Legion, Kingston, right after insertion, theoretically started with forced xmp profile and 4800Mhz CL36 clock without any interference!
Latency was lowered relative to Samsung, but the timing remained at the same level as Samsung.
Perhaps the change in timing is software blocked by Lenovo and they adapted to what Intel assumed. As mentioned earlier, the 12gen 12700h/12900h processors support DDR5 up to 4800Mhz.
However, other vendors like Gigabyte have made full use of XMP possible. For example, a Gigabyte Aorus with a 12700H processor could work with DDR5 6000Mhz memory (I saw it on some official Intel table).
A 12900k processor in a desktop computer also allows for much faster RAM even though Intel says a max of 4800Mhz.
So much depends on the manufacturer and other things imposed in advance.
Forget about the timings I wrote in my last message, I’m dumb as a stone, those were timings for the big brother, not the SODIMM. The SODIMM datasheet is not available (404) and since we can’t run anything to read the SPD data we can’t know right now what the profiles in there are (unless there’s someone, somewhere, that posted them, or they’re printed in the box).
But yes, things vary from one manufacturer to another, but if I were to hazard a guess I’d still bet that OC being disabled is what prevented the memory controller from picking up anything higher than 4800, even if there was an XMP profile present for it.
If you ever get to boot the laptop before needing to send it (or even after) try to just enable OC and memory OC to see what happens. Although it may be interesting to invest in a cheap programmer… just in case 
.
I guessed about the RAM data
I’m also convinced that access to OC/UV RAM/CPU hides many possibilities. But you have to do it without the need for permanent writing (similar to desktop motherboards).
For now, I have to revive the Legion and I hope that these experiences won’t discourage me
I don’t believe desktops to be different in the way of where data is saved, they do have better recovery procedures, specially enthusiast level boards, double flash chips for the firmware and the like too; but I’m no expert by any metric.
I also hope you and Ravenith get your machines in working order again.
Bringing the laptop back to life is a matter of time - whichever way it is.
I’m going to drink
The topic is opened…
Update:
I’ve had several conversations with Lenovo service.
Indeed, to restore the NVRAM settings, you need to program it. To do this, you need to remove this chip and solder it back. They know it but Lenovo’s service policy is that they prefer to replace the entire motherboard 
So now I’m waiting for a service technician to come to my house and replace motherboard…
Great Lenovo! I will have a new board, cpu and graphics because i clicked save in advanced bios settings and the laptop failed POST… 
…but OK, those settings were top secret 
It needn’t be new, could be refurbished, think of what will happen to yours afterwards, they’ll take it and at some point I bet they’ll prepare it to be used in another repair (clean serial number / asset tag, etc. perhaps to be filled by the technician after the swap).
But hey, at least you’ll the laptop back to life!
I thought about it but on the other hand it’s a rare CPU and card model and relatively fresh. Certainly very few of them are used.
I don’t know why I should care about the serial number, etc. But on the other hand, I’m not entirely happy with how they want to handle it…
I can always ask or even want the motherboard to have to be brand new. It probably won’t come out of the box. I won’t check it…
It’s all a bit fucked up…
I have no experience with Lenovo, but other brands ship the spare part to technicians looking like new (and yours very well may be since it’s a new-ish model). With Dell, after the first boot when the motherboard is replaced, the technician has to access the BIOS and is asked to input the service tag of the device (an ID), that UI doesn’t appear anymore afterwards and then it’s ready for the user.
I wouldn’t be worried, and warranty-wise nothing changes.
'…to input the service tag of the device (an ID), that UI doesn’t appear anymore afterwards and then it’s ready for the user."
“I wouldn’t be worried, and warranty-wise nothing changes.”
I hope so … 
An additional problem may be liquid metal on cooling … what will the technician say …
If this guy will chill, turn a blind eye… then maybe we can get along with other things… 
By the way, my job will go fuck up 
…Sick thing… in Macbook you type key combinations to erase NVRAM…
In Lenovo you need to replace the motherboard…
What about Colleague Ravenith, any progress?
Fresh info from the official Lenovo Care Premium Service: “… you can replace the thermal paste on your own without voiding the warranty, similarly liquid metal (not recommended but correctly applied does not exclude the warranty)…”
Moving forward a bit…
Is there an option in BIOS to skip saving changes (advanced option) to non-volatile memory and set to UEFI BIOS (possibly another option)… ???
I concluded that no…
Playing Thaiphoon Burner is rather complicated and too risky so…
Staying with the BIOS. When setting DDR5, remember that unlike DDR4, Gears options cannot be set to 1!
DDR5 memories run on Gear 2 or 4. The downside is that the memory controller is limited in bandwidth by half (gear 2)… compared to gear 1. So DDR5 makes up for it with high clock speeds.
For example DDR5 5600MT should run at CL40 latency and 1.1v (OEM). So when you set latency that and max. timing at 5200MT and leave GEARS at 0 (auto) theoretically the laptop must start. In practice, nothing is certain…
Serial, MTM etc… can be restored with LVAR or the Lenovo U1 tool
I’m in the game
This mod doesn’t work.
I can’t access Advanced/+Memory Configuration/+Memory (Memory Overclocking Menu)
Can you see it again…???
Thanks!
UPDATE:
It looks like this BIOS hasn’t got XMP options and RAM latency settings. But SA GV should allow you to force DDR5 to run at 5200+. However, it is still risky in case of POST problem…
I enabled SA GV in AUTO, frequency to 5200MT, Gear AUTO and LPDDR5 clock limits from 2000 to 0 (auto) but the clock turned out to be unstable and drop below 4800Mhz in windows (CPU-Z). Going through POST took a long time, it made me scared so I won’t undertake to force manual settings
It remains to wait for Lenovo to decide to unlock the potential of RAM. Intel is already talking about 12gen cooperation with 5200Mhz RAM! I still think it can handle even higher clock speeds than this…
Someone managed to unlock undervolt options in this Lenovo Legion? As I know Intel blocked UV on 12gen CPUs, but actually there’s a setting even in the normal BIOS called “Cpu Unlock”, however, you can’t still control voltages via Throttlestop. Maybe there’s another hidden setting?
I think there is an option to change the CPU voltage in the advanced options, but I’m not sure. It is still risky by saving these settings in NVRAM (I wrote about it above).
I wasn’t interested because Throttle Stop itself gives you the ability to set TDP: TPL/Power Limits Controls/Long Power PL1
12gen works great in the 18-26W range. I tested it in many games and there is no need for it to use more power, it has plenty of it. It’s also a good idea to turn off the turbo. It works well in most applications and games, and in windows it allows you to significantly lower the temperatures.
Personally, I have turbo turned off under windows, in games I turn on and use the Long Power PL1 18-26W range depending on the game.
I also recommend undervolting the GPU in MSI Afterburner. There are some tutorials on youtube. These two things give great results in lowering the temperature (CPU and GPU are on the same cooler so they influence each other), but also help to achieve consistent and better performance.
Thanks for the tips, Focus! Yeah, I tried to boot on the advanced BIOS and noticed some stuff for changing voltages directly there, but didn’t want to touch anything as I read all the story about Memory frequencies being unable to boot PC and restore settings even after a CMOS reset…
Also, I don’t really have problems with thermals, in most cases my CPU has spikes of 80-85 while on average It runs low 70s while gaming, GPU being even lower (sometimes it doesn’t even go past 70) so that’s why I don’t wanna mess with this stuff if there isn’t a secure way. It was more of a curiosity, but I guess I’ll try to play a bit with PL modes as you said (should be possible to do it also on Intel XTU I guess)
The Bios has that setting, the get hidden on non HX cpu…
If you unhide them and try to change anything, it will brick
Anyway, if someone will read this and be interested in CPU undervolting, this is all I found (nothing particular):
By loading the advanced settings with the .cfg file (thanks to @AARCH64_EL3 and @JRMoore), you can navigate to
Advanced → Power and Performance → CPU - Power Management Control → CPU Lock Configuration, here you find two settings, CFG Lock and Overclocking Lock.
By setting these both to disabled, UV/OV will still NOT work. (maybe there’s another setting?)
You can (probably) try to manually undervolt by navigating to Advanced → Overclocking Performance Menu → Uncore → Uncore Voltage Offset, and setting your value.
But the problem is that probably if you set a far too aggressive value, your laptop won’t be able to POST, and that value would be saved. I don’t know if it would fail to POST even by putting a minimal value due to a sort of “protection lock”, trying this is too risky for my case. Good luck