I just received my fancy new AMD Ryzen 7 6850U based Thinkpad X13, which I so painstakingly researched before buying.

When I first booted it up, it took about 1 minute before the Lenovo logo appeared. This was unexpected. Then it took another minute to reach Windows. Also unusual compared to the last Thinkpad I had.

When I booted Slackware Linux on it though, I began seeing Hardware Error messages, with the reassuring message "Corrected error, no action required."

Has anyone seen these messages before on other machines? FWIW there are no BIOS updates available for this computer yet.

See attached screenshot.

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So, I have the T14s version of your laptop. Had the same issues on the first few boots hanging or taking 40+ seconds to post, was utterly deflated that I had bought a $2000 pile of garbage. I, luckily, have had no further issues since getting EndeavourOS installed. However, a quick search of the error messages says that IS NOT uncommon with these. Not that I can say I ever found anything that truly describes what EXACTLY "unified memory controller ext. error code: 12" means. Now, I do believe I had a firmware update for something (wasn't the "bios") in fwupd when I first installed. I would at the very least call Lenovo to get their opinion, I can't say positively one way or another if it's actually a bad CPU unfortunately. But given how much you most likely paid for this thing, you deserve a fully functioning laptop.

This is not that simple, if after a firmware upgrade or another OS works perfectly it is a fully functional laptop.
I would suggest to try to boot different live CD-s (for example ubuntu 22?). Try BIOS upgrade and probably also cpu firmware upgrade.
Also probably I would try to run memtest. Is it overclocked?

There are no bios upgrades, OP ssaid that in the first post.
Laptops don't support overclocking except (some) gaming models. This is a Thinkpad, as it says in the OP.
He's having issues with POST being exceedingly slow, this is OS indepenedent.


Did you even read the OP?

I did not speak about bios upgrade only. I mentioned that as one option, but there are others to try. Obviously, if it really wasn't available, it wouldn't be possible. I did not check it myself.

I ended up returning the Thinkpad the next day. Once they receive it and accept the return I'll just order an Intel-based Thinkpad. Right now there are a bunch of new models being released, and a bunch of coupon codes like THINKBIGDEALS that make these more affordable.

For the record, I have certainly seen those errors in other machine with varying levels of hardware. Linus' kernel talks to you a lot, giving debug level of output. Windows, OTOH just does it's business and only talks to you when it's going down in flames.

When you have really bad hardware (as I have had) the kernel throws hissy fits, gives drastic warnings with exclamation marks, but still manages to boot usually with a "one wheel on my wagon, but I'm still rolling along' approach.

An MCE means the software detected something like a hardware fault. As a hardware guy, let me assure no software ever has a clue what the hardware is actually doing, much less what is wrong with it. The hardware is going much faster anyhow. I'm pretty certain it's not your cpu. It's a "Something wasn't perfect" type of error. And software is not a good judge of what's perfect and what isn't.

The biggest problem I see is that you're paying too much attention to boot messages. I'd like to be there when your item returned as faulty is being sold off.

Incorrect, this message appeared on the console after boot-up.