Hyper-v performance issue?

Hi everyone. Quick question on some perf issues i've had for quite some time. To be fair i was using esxi 5.x and had similar issues. My vm server is running a first gen intel core series cpu (i7-920) that is overclocked to 3.8ghz. Just so you don't have to look it up it has 4 cores (8 with hyper-threading) I have 3 vm running on this server. 2 of the VMs pretty much do next to nothing they are just there for when i need to do some testing (one has server 2012 R2 and the other has ubuntu). The main vm that i'm having issues with has Win 8.1 enterprise. I don't have a lot of things installed on it but i do have plex (when i want stream videos through my house). At least for 1 stream (never tried more) it works just fine. When i remote into the machine and run some things its so dang slow. For example a fresh install of google chrome will constantly use 50-60% of the cpu. Somtimes it will peg it. Its go so bad i know use firefox most of the time though a lot better the cpu usage for firefox is still not where it should be. Now i know chrome is turning into a hog but it shouldn't be that bad. I've had this problem for quite some time (with windows 8 too). I think i have two vCPU assigned to this VM, 2 to Server 2012, & 1 to Ubuntu but like i said they hardly do anything. I have 4GB assigned to Win 8.1, 8GB to Server 2012, & 4 to Ubuntu (the machine has 24GB Total). Any ideas? Is the I7-920 getting so old that i should have these issue?  

Edit: I'm running Hyper-V on Server 2012 R2