Why does the computer lose its connection to the Internet gateway?

Question

Computer networks

Hello, is this a problem?
there is a company in this company about 8 departments and about 100 PCs, in each department there is a managed cisco switch, for 8-24 ports, the question is as follows:
Recently, a strange thing has begun to happen. Some computers, about 10, simply lose their Internet connection (an error appears, the connection to the gateway is lost) and everything does not go to the Internet, it does not see the internal network, it does not see local balls and does not go anywhere until you distort the cable, or until you turn it off / on network. This happens on certain computers and at exactly one time. All computers are the same configuration, the network card is the same everywhere and the software is the same everywhere. There is a Mikrotik router in the server room, all the rules are filled in on it, and so on. There is a CISCO router, a DHCP server is raised on it.
PC configuration
1) Mother plan: ASROCK 960GM-VGS3 FX
2) RAM 4 GB DDR 3
3) Processor: AMD FX6300
4) SSD: 60 gb

By the way. sometimes there is a BSOD when you turn off and on the internet cable. I won't give you the exact code.

PS. I found a temporary solution to the problem, so to speak, CRUTCH. You just buy a cheap network card and everything works perfectly with it, but this is not a solution.

Thanks in advance!

Answer 1

DHCP lease 99.5%
Look at the address lease time and compare it with the locale loss time after turning on the PC, according to the symptoms, the PC re-requests ip from the dhcp server and for some reason does not receive it or does not accept it.
And another network card solves the problem, most likely by the fact that it has different software (drivers),
so as an option, update the network card drivers on problem PCs