I like this project and the dedication of the dev and started mining with a couple of old PCs, tablets and notebooks a while ago.
While some CPUs + OS work fine with xmr-stak, others don't.
With the generic 32 bit version of the YAM miner I was able to let even those machines mine which don't work with xmr-stak versions.
For example: Severals Win 8 or 10 tablets with Atomic quad-core CPUs.
Or a Dual-core on Win XP.
You can download it here:
https://mega.nz/#F!h0tkXSxZ!f62uoUXogkxQmP2xO8Ib-g
You just need the yam-yvg1900-M8a-win32-generic.zip folder, none else.
For mining CREP the YAM.bat needs to have the following entry:
yam -c x -M stratum+tcp://your wallet address:w=worker-name@pools-URL:3333/xmr
Example: yam -c x -M stratum+tcp://cr4Wp65se8m6VDJqYU4fvrY8dRJkVbPaEF1xXeHNs64KSz6kY2SVRXS9ZGAizq1oMN9avU8VJ9sBBMvvwfkqfB6r2vEoAwnjZ:w=Atom07@crep.miner.rocks:3333/xmr
The YAM miner has a fine-tuning mechanism to optimize the mining results.
And you need to be patient for some minutes as this miner tries to mine XMR for its dev for some rounds and contacts other pools.
And as a big help crep.miner.rocks shows every single worker/PC and allows you to see its unique hash-rate.
Now, dig out your old Win8 or 10 tablet or old single core CPU machine and try it.
I love to hear about your results.