How bad is it to install a hdd from one pc to another with its OSs?

[kharl]

Hi!
I had a Hp Elitebook 8460 with windoes 7, nice installed no errors all smooth, and i got a new laptop, an elitebook 2570p, smaller but slighty powerful than my previous one.
Both ddr3, the old one i5 the new one i7

I decide to see how it behaves if i just remove the hdd and installed in the new one, despite the video driver, all seems to works fine... what are the cons of keeping hat for long term?

 

[SIW2]

intel 2nd gen QM67 to intel 3rd gen QM77.

should be ok.

 

[siliconbeaver]

I did swapping Win7 OS HDD often within HP PC family (laptop, desktop Elite from 8000-8300, G1-G4).

desktop to laptop, no issue. after boot, needed laptop keyboard/mouse to finish. just selected/clicked to install drivers needed.
desktop to desktop, no problem to boot. but if no PS/2 port (such as G2-G4 mini). then no way to continue. had to fail.
on 8000-8300, G1, there is a PS/2 port, I could connect a PS/2 device (either mouse or KB) to finish driver install.

a usual problem, USB ports NOT working after HP OS HDD swapping. no matter you use a tool (such as paragon) or NOT. HP is a problem.
with a PS/2 port, and a PS/2 device to finish driver install. HP USB port will work after driver installed.