Question Thinkapd T420

[Devmalya]

I bought used machine last month thinkapd on olx (india version of craiglist) , after its delivery windows 10 installed cpu usage gets to zero system freezes and thouchpad left click button stops working as left menu only the right menu appears , after the installation of windows 7 same thing goes on i exchanged the ram with my t410 ram (good condition) , system didnt freeze but cpu usage remains zero . i saw 2 core were locked in resource monitor and I unlocked them but still reain the same issue . Cpu usage to zero.
Any ideas or sugesstion welcomed.

 

[hang-the-9]

Well first thing I would do is contact who you bought it from and return it. If you can't manage to do that, try checking for a newer BIOS.

 

[geofelt]

Test for basic functionality with memtest86.

The keyboard on those units are easy to replace. I just replaced a t430s keyboard for about $30.