installed the new 0.3.9 agama wallet and my hashrate exploded from 3.1 MH/s to 170 MH/s

Was there a change in the algorithm itsself that i now have a 55x improved hashrate?
Thanks. I have 656 MH/S.
Which processor are you using?
I am using AMD Ryzen 1950x 16-core. It's still ok to use it for mining VRSC at the moment. As difficulty consistent going up soon it will be obsolete.
I don't know that it will become obsolete anytime soon. Right now, there is work ongoing on a GPU miner, and the last I heard, GPUs are looking like they are likely to be competitive with CPUs, but probably not better when comparing similar cost/power usage.