Post all the info for you system, mobo, CPU, memory amount, HDD or SSD, what windows version and 32 or 64, did you upgrade, clean install, both. You could have 1 gig of memory and people here could go crazy looking for an answer when you don't have enough, so start with some info please.
Sorry. tell him to ignore my post and don't post any info because of my example. So have you got this solved yet ?.
Not that unusual if you have just upgraded. You are going to have to write a short story and supply some info about the recent history of your system. If the system is lagging them you are using the slowest HDD available. With that processor a standard HDD is such a waste of processing power. Post upgrade you could be installing updates in the background etc. etc. etc
The only time i experienced "System" with that much of disk activity was because of bad sectors in HDD
Try to disable automatic updates, or just remove Ethernet cable to be sure... reboot and let us know if still high ram and disk usage. Do u have an ssd or hdd? P.s. u can check disk process write/read with process hacker
Once something like that has happen to me it was one off after restart everything working alright up til now
use Process Explorer instead of task manager hxxps://technet.microsoft.com/en-us/sysinternals/bb896653.aspx it will show alot more info specially where that 50mb of network is going and what threads are chewing cpu
"system" process means driver issue (got that info from some ms build// conf-video) - i would recommend that you update your display driver.
I had a similar thing happen a few times in the past 2 weeks. For me it was my memory (4GB) that all of the sudden was being used up by a service. Only way I could recover was to reboot. I've yet to see what triggers it and not seen anything in the event viewer that indicates a problem.
had a similar thing happen on my system, ram usage went up and up till system became unusable I had to roll back from a beta amd graphics card driver to sort it, using a stable driver and now seems ok never had a problem with beta drivers before
what kind of video card is he running? standard HD video or nvidia or ATI.....this why is always good to run the compatibility test if u are installing win10 for the first time.
The Disk driver needs to be thoroughly checked and the upgraded system possibly has some bug. Please, post your local drive image here