Your event logs (app & sys) did not seem to be exported properly (they're both 0 bytes in size). The latest crashdump provided is from the 20th, with the one before that from the 3rd.
The Aug 20th crashdump reports a memory management issue that occurred when the process RzSynapse.exe was running. I am very well aware of Razer and their poor
driver code, but you should still check to see if there are any updates for your Razer product(s) as well as firmware, since that has relieved a lot of issues for Razer customers.
The crashdump from the 3rd reports an issue where your Hamachi driver was not properly handling what appears to be the system going into a low power state. As a result, it hung up on a power IRP and therefore the system crashed. The driver itself is from Feb 2009, which is pre-Windows 7 release date driver. You will definitely want to consider updating it.
Other than that, I'm not able to determine the cause of your most recent crashes. Given your latest one was a memory management issue, you may wanna look into running
Memtest for a few passes on the machine, but that's probably not a very appropriate option with what is probably a production server (am I correct?).
I may be able to provide some more assistance from your MEMORY.DMP file. Can you verify that it is the latest date (at least not from the 20th)? Also, given you appear to already have Windbg installed, run
Dumpchk on the dump file, just to verify its integrity before uploading it to some 3rd-party filesharing site. You should find it in the same directory where the Windbg.exe executable is located.
Btw, before we continue, or before you even upload the crashdump, be advised that a kernel dump has a lot of information on. If this is in a production environment, you will want to forgo uploading it as it'd be quite a security risk and would probably be against company security policy.