X250 Going from i3 to i5 or i7

[cfds]

Hello all,

I am thinking to use my X250 as a desktop set-up. I have been trying to sell it but nobody seems really interested spending 250€ for an older thinkpad. They are throwing computers to your head nowadays especially after a lot of folks been buying laptop to work from home...
So instead of giving away a fine little gem in perfect working condition I am thinking to use it as a desktop replacement.
As a desktop I have currently a 24" all in one HP TouchSmart with a full HD touch display. When new in 2005 the full HD display was stunning but now its shows its age.
The only thing is that the CPU from the X250 is the smallest i3.
Would I see a big performance jump when upgrading the mainboard to a i5 or even an i7 board?
The X250 is equipped with dual battery's and dual SSD's so its not really slow.
Looking forward for your comments,

Cheers

[RealBlackStuff]

I have an X250 with i5-5300U, FHD-touch, 8GB RAM and W7-Pro.
Runs fine with anything I throw at it.
i5 will definitely see a major improvement over an i3.
But I doubt that i7 will bring much advantage over an i5 on these machines.
From the CPU options, avoid the i5-4300U (old HD 4400 GPU and max 8GB RAM).
All others have the HD 5500 GPU and can have 16GB RAM.

[cfds]

Ok, bought a used i5 board for the X250.
Can I just drop in the board and use the current SSD with the windows 10 image on without a problem?
Will I get a notification about the windows license key?
I also found a palmrest with a fingerprint reader, that will also go onto the X250.

[RealBlackStuff]

Replacement will be a drop-in.
The SSD should work without (hardware) problem.
However, I am not familiar with W10 (and never will be!) but I assume Micro$haft might protest a bit.
You might need to check your BIOS settings for the FPR.

[cfds]

The transplant has been c/o with suc6...the laptop fired up after the 1st attempt and windows did not complained about the key.
I did had my BSOD which I have had occasionally before, critical process failure followed by a unable to find SSD during the reboot after the BSOD. 2nd start after full shutdown is normally fine.
As I transferred only my SSD and RAM stick - all the other components were already present on the replacement board I suspect or my SSD.
For now I will see how it behaves...
Now only finding a good desktop display and keyboard, I believe I have a worthy upgrade over the HP touchsmart all in one desktop from 2006.

[RealBlackStuff]

Sounds indeed like a duff SSD.
As for a desktop monitor, have a look at e.g. Dell U2412M or U2415, they are 24" 1920x1200 16:10 IPS.
They are already a few years old, but excellent screens.