Do you know who manufactured your mem? I seem to have gotten Hynix, and I only saw 32 kh/s - Granted I only went to 1200, but the diff between 1050 and 1200 was maybe 2kh/s tops, so not sure how another 100mhz would make such a big difference.
Mine's Hynix. 100 Mhz will bump it sure but not to 40. I am using single thread on VII. I am on 19.3.x drivers.
Just Update win 10 pro (to last version) + driver to 19.3.2 version from 18.6.1 because no need for ppt table and read that this driver is OK. Update OverdriveNtool to last 0.28.beta 1 too.
Strange: CNR on 19.3.2 work just like on 18.6.1 driver but Turtle algo with 19.3.2 driver on Vega 56 (64 bios) or Vega 64 (Asus) drop hashrate from 18 kh/s to 10 kh/s
Did someone try turtle algo on 19.3.2?
Seems like I am not the only one. I had similar results. L28+28 gives 10-11 Khs. Try 26+26, it would work fine around 17-18.5 Khs still not as good as other folks who can get L28+28 with earlier drivers.