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Edit: after getting the laptop back from repairs, and setting some non windows optimized settings in the bios before plugging my SSD again, this time grub worked and linux booted without bricking the system.
More details here:

For indexing and search purposes, both +Theodore Ts'o and I got a lenovo thinkpad T540p (t540), and when we booted from a linux drive as the main drive inside the laptop, it bricked the laptop by only showing
"To interrupt normal startup, press Enter?" after power on.
From there, no way to get the bios, no way to get past this screen even after putting back the original windows8 drive that came with the laptop.
Ted tried to removing the cmos battery but it didn't reset/fix the board, it had to be replaced. We think something, likely grub (Ted tried grub2) but hard to say for sure, corrupted the bios/firmware in a way that isn't reset by power cycle or removing the battery (it's not the linux kernel because it never booted on my laptop, and for Ted he was able to boot it from a secondary drive).

Ted had his motherboard serviced, the laptop booted again, and when he put his drive back carefully and booted from it, it bricked the new motherboard.
He did get linux to boot from a secondary drive before that happened, I didn't because I put my drive directly in the main bay. As of right now, we both have a bricked T540p.

I haven't gotten my laptop back yet, we're not sure what causes this, but it could be grub that is causing a MB bug (I believe neither of us got the grub boot screen).
This is worrisome. I'll +Tejun Heo to pass the word for now and will update this when we know more (or Ted likely will too).

Ted's experience (with more details, because my laptop arrived and failed 24H before an international flight, so I had little time to debug further after lenovo support said "we need to replace the motherboard", is here:
Calvin Walton's profile photoTheodore Ts'o's profile photoJason Altorf's profile photoMarc MERLIN's profile photo
Ouch that is very scary. Lenovo laptops used to be very Linux friendly, right?
I don't have any clue. However, I'd put my money on the possibility that they only tested under Windows, and have a bug that Windows doesn't trigger.
For the record, the disk involved also had a clean install of Windows 7 SP1 in a small partition, and things didn't start going south until I put grub2 on the MBR.   This disk also boots just fine on my T430s.  And I was able to boot off of a snapshot of my root file system placed on a external USB disk.  But when the disk containing the grub2 bootloader was placed in the primary HDD slot, it apparently bricks the motherboard.   I've brick'ed the motherboard three times in the space of a week.   So I'm now looking for anyone who has been able to successfully install Linux on a T550p before I do more experiments.....
In the back of my head, I suspect that might be the motherboard's way of refusing to run untrusted MBR code, intentionally or not. I can't think of any other reason why the exact content of the MBR would matter as long as the checksum is OK.
+Jean-Baptiste Quéru the laptop does not even boot to its own bios or when the drive is removed when it's in that state.
+Theodore Ts'o My next try on Jan 3rd when I get my laptop back is to boot it with lilo instead of grub2. I might even try booting it with the drive without an MBR, just to make sure I still have a bios after that attempt, before adding the MBR back.
Does this laptop have a UEFI bios ? If so, this sounds like you are missing some EFI parts (like the early disaster of not been able to run Windoz on the first Intel MacBookPro)
+Fabrice Di Meglio It does have a UEFI capable BIOS, but so does the T430s, and it also is supposed to support booting via Legacy mode.  It wouldn't surprise me if there are bugs in this new BIOS which is causing problems.  Apparently Ubuntu did certify the T540p using the 1.01 version of the BIOS, but my original motherboard had BIOS version 1.11, and the replacement motherboards had BIOS version 1.08.
My T440p is arriving soon after New Year's. I have no plans to run Windows on it, so we'll see what happens when I try installing Linux. (I also bought with the cheapest HDD Lenovo offers, which I'll replace with an SSD...)
my thinkpad boots windows 7, on which i run oracle's "virtualbox", inside of which i boot debian 7 and freebsd 9, where real work can be done. i wouldn't begin to imagine that i could safely control all this hardware gadgetry with a bare metal operating system that lenovo hasn't tested it with.

you guys are brave. i hope it works out for you. let us all know, ok?
+Paul Vixie, I've been booting and running linux natively on thinkpads since 1996 (a bit like I've been compiling my own kernels since 1993 and still do it to this day out of habit), so booting windows just to run linux inside isn't something that would occur to me now :) (I run windows in vbox if needed, but my native OS is the one I use the most and for which I want native driver performance on).
Thinkpads have worked so well with linux for the last 10 years of so that it didn't occur to either of us that they would start having issues now. Obviously that was maybe overoptimistic.
Either way, yep, we'll sure let you know, this is why I made this post public.
so, i built kernels from source starting in 1986, but i gave it up in ~2004 when freebsd caught up to linux in terms of modular kernels. and i did run bsd/os native on my DEC HiNote-II Ultra, where most of bind8 was written. so i'm hip to native unix. really.

it's just that suspend/resume, bleeding edge wireless, multi-monitor video, volume control buttons, fingerprint readers... all tend to lag a year or severalyears behind on unix, compared to windows. now that virtualbox lets me run anything i want for getting work done, i've been taking the easy way out as far as speaking to the hardware itself. ymmv -- certainly my penchant for bsd-derived unixes costs me more hardware-support lag time than linux would. noting, i ran opensuse native for about five years' worth of thinkpads, but i eventually tired of the hardware support struggle and i've never looked back.

windows vomits blood, from a quality and innovation standpoint. but it does run chrome and virtualbox very nicely. i'm speaking to you from a W520 plugged into a docking station with two 1600x1200 monitors and an ibm model m keyboard and logitech mouseman 3-button mouse. i've never had it better.
+Paul Vixie I hear you on the hardware support. Linux has definitely been much better in the last 10 years, but it's often been a bit more work to get everything to work on linux than windows, no question there.
As long as you're ok with the loss of IO performance due to the VM, and don't have an issue having MS boot your machine (I do on principle, but that's just me), what you're doing is indeed more than reasonable.
That being said, Xorg has supported monitor hotplugging and multiple monitors on a laptop for a fair while now :)
the only thing i don't virtualize is real time packet processing, like busy dns servers or anything involving bpf/pcap. but that's all server stuff. for my laptop, most of what i use virtualbox/unix for is dev-test and "konsole". the place i need strongest performance is in windows, because that's where professional games run. when SteamOS takes over the universe and i can run games at full FPS without having to do it in windows, i could imagine making windows live in a VM and letting unix be the bootup.
Crossing threads again: +Theodore Ts'o was doing a debian install so presumably (Ted?) using the debian build of grub2. +Jason Altorf reports success with OpenSUSE, and +Dominik Hannen with ArchLinux. +Calvin Walton didn't specify AFAICT. +Marc MERLIN, which did you use? (I'm wondering whether a specific build of grub2 is involved. Not that it would be grub's fault that the machine bricks itself...)
+Michael K Johnson I'm a crazy Exherbo user developer. T440p. Boot loader was gummiboot manually installed in my setup, but boot also worked fine with non-efi grub2.
I had grub2 Debian testing too using legacy mbr with 4 parts on 1tb ssd
Running the T540p with Opensuse 13.1 using GPT and grub2 installed to the standard 1TB drive. Bios revision is 1.09
After getting the laptop back from repairs, and setting some non windows optimized settings in the bios before plugging my SSD again, this time grub worked and linux booted without bricking the system.

Long story short, X came up with the full resolution, wireless works (with 3.12 at least), ethernet is still the kind of wonky but mostly working e1000e.
Sounds comes out but quality is indeed crap. Apparently it needs some special dolby driver that linux doesn't have. Grumble....
I guess I often use headphones, but still...