wierd problem after cpu swap and bios resset

So i swapped i 7 back to i5 for test purpose and made a bios resset (battery removing)

Now i have a problem: when i press power butmn, indicators lights up but no bios screen appears. after multiple times pressing power butmn bios can start up ( without any conected devices)
and some times i have usb ports problem: they doesnot work...

what can it be?

also at first succesfull boot i found in device manager that chipset and usb 3 drivers has a warnings . but i solved this problem by reainstalling drivers..

any help will be welcome/

 

Well, this is why I'm afraid to work on my own machine hardware. I'm terrified to take anything too far apart.

You could try my trusty standby for situations like this: Discharge the system, Remove all power supplies and battery then hold the power button down for over a minute. Restore all power supplies and try it.

I know I know, but it has worked for me twice having very strange problems.

 

is the UEFi boot much better then legacy?

will try bios resset again.. when will swap cpus back today evening.

 

I have similar problem when some component not sit tight. Check the connections.

 

Can't tell any difference between Legacy and UEFI, that I can notice anyway.

Yeah, I was going to also say what Baii suggested.

I guess you do have to take quite a lot apart to do that swap.

 

well i localized a problem
when all devices plugged and pc is booted in windows = restart going well
on cold start =no boot
cold start without power cable=boot successful



may be some bios option?

also how can i check my usb ports? i have some mission critical files backing up=/