The current pre-release of the client ("pioneer" in the version) is only compatible to itself. So you can only play with other testers. Please be aware!
Run some software such as aida64 to see if you are thermal throttling, this will determined if your thermal past has degraded or your vents are blocked.
Also if you are going to keep using this laptop upgrade to a 1TB ssd, they are quite cheap; However it really is time for either an upgrade or build a new PC.