csrss.exe, winlogon.exe and nvvsvc.exe How do I locate them?

So I recently have been noticing a weird, little box on my desktop. And when I drag it to a bigger version, its just a black box. Kinda like a blank cmd.
After that I went to my Processes, and found these 3 .exe's without any paths.
Now I think, that the nvvsvc.exe is Nvidia drivers or something like that. And winlogon.exe, is a part of Windows login subsystem.
But when I googled csrss.exe, I found a lot of threads about it as a Trojan.
So I'm asking, how can I locate these .exe's, since when I right click on them, and press show location, nothin happens.
Thanks in advance!

And sorry for my bad english.

Legit csrss.exe is located in \%WINDIR%\System32\

All 3 processes might be a malware if located in false folder. You can type process name in file.net and find legit path and process description. Regarding process location, I recommend to use utilities either Security Task Manager or Process Explorer to find the process location.