The effective hashrate of recent JCE is back to >98%, close to 99% efficiency, as before. And as all current versions of miners so far (xmrig, srb, teamred...).

I'm polishing my fix of the regression on CN-Fast on Vega. Looks like my auto-hybrid introduced in the experimental -x, -y, -z and -sync versions works bad in such case, so i introduced an override --legacy to force the good old non-hybrid mode.
I benched it to be either a little faster or slower than b12 depending on the cards and algo, hard to tell if it was an improvment or not. This way i'll let the user choose.

edit:
@cryptoprofitswitcher: online is the b13, partial release with just the .exe Inside
you may try with undocumented parameter --legacy to check if it restores the speed on your dual Vega.

@other: it contains a very small optim for Vega, and for non-heavy algos, if you want to take a look.
the --legacy may also give a few extra perf, but it's ignored for heavy-class algos, it's just for CN and CN-Light

if it solves the problem, i'll make it a full documented release.