ThinkPad L540 - CPU upgrade

[DellThinkpad]

Seems like it's only possible to upgrade those CPUs which are in some of the original configurations of the L540.
I tried an i7 4700mq but the laptop won't boot.

[DeathBringer]

Post screenshots of first (CPU) & third (Mainboard) tabs of CPU-Z with current CPU.
Tell sSpec of your i7-4700MQ
Explain exactly what happens when you try to boot with it.

[DellThinkpad]

sSpec of the i7 is SR15H
Laptop turns on for about 0,2secs (Power button lights up) and then turns off immediately without trying to reboot again.

This was not really a mod request but I didn't know where to let you guys know. Probably I'll just buy another i7. You think it's save to mess around with the BIOS? I don't want to brick this thing^^

Thanks very much for your reply!

[DeathBringer]

This BIOS has support for your i7-4700MQ.
Try this algorithm:
1) remove AC jack, Main Battery, and CMOS Battery
2) remove HDD and all DIMMs
3) install new CPU
4) wait 10 mins
5) press and hold power button for 30 sec.
6) install CMOS Battery and one DIMM only, inject AC jack (without Main Battery!)
7) try to boot your laptop.

[DellThinkpad]

I tried it exactly the way you described but it won't boot.

[DeathBringer]

So this CPU is dead.

[DellThinkpad]

I don't think so. Will try in a different laptop soon.

[Fenderidge]

Seems like it's only possible to upgrade those CPUs which are in some of the original configurations of the L540.
I tried an i7 4700mq but the laptop won't boot.

I've had the same problem a couple of years back. Unfortunatly I had to buy a new one. Never got to the bottom of the problem.

[DellThinkpad]

I've had the same problem a couple of years back. Unfortunatly I had to buy a new one. Never got to the bottom of the problem.

Can you be a bit more specific please?
You tried two !confirmed working 4700mq in the L540 and one did work and the other one didn't?

[ChadParks]

This BIOS has support for your i7-4700MQ.
Try this algorithm:
1) remove AC jack, Main Battery, and CMOS Battery
2) remove HDD and all DIMMs
3) install new CPU
4) wait D bal Alvenda Review 10 mins
5) press and hold power button for 30 sec.
6) install CMOS Battery and one DIMM only, inject AC jack (without Main Battery!)
7) try to boot your laptop.

Thanks DeathBringer, you saved my life! Your step-by-step instructions revived my dead(bricked) lappy.