Hynix AFR on X299 OC

[mackerel]

Modules are Corsair Vengeance RGB 8GB 3000C15 modules. Thaiphoon Burner reports them as Hynix AFR. I have 8 sticks in an X299 system and I need more speed. I've tried a quick search but not got far. What's reasonable expectations for these chips?

On the practical side, setting 3200 16-18-18... booted ok. 3400 at same timings crashed during Windows boot. I got to desktop relaxed further to 18-20-20... then I had a look t voltages. Reported ram voltage was a bit under 1.35V so I gave that a small bump to compensate. SA was just under 0.8v, which seemed really low compared to mainstream boards. Is X299 different or is that just low? IO was around 1.0v by default.

I just tried bumping SA to 1.1v and IO to 1.05v, as well as the ram voltage to 1.37v to allow for the slight droop. That has allowed me to boot at 3400 16-20-20... I suspect for my application bandwidth is more important than timings, within reason. I'm also running 2DPC although I've not tested if that helps over 1DPC in current use case (it does a LOT for Prime95 like loading). Because I have a stupid big Noctua on the system it isn't trivial to remove ram sticks...

 

[Woomack]

How high SA is setting the board at auto? It should automatically set too high value but still safe and good enough to push the RAM higher. I think that my ASRock was going up to 1.3V when I set 3600+ memory clock. Don't remember exactly.
Hynix will require a higher voltage to set a higher clock and lower CL. Additional timings won't change much because of higher voltage so you can count on something like 3600 14-18-18/14-19-19/14-20-20 1.40-1.55V ... or maybe CL15. 4 sticks should still go up to 3600-4000 at a higher voltage but not all IC can do that.
Depends on IC, new Hynix can make between 3600-5000. However, there are at least 5-6 different IC on the market right now and some of them are marked about the same. Like new and old AFR, MFR or CFR.

 

[mackerel]

On auto or XMP SA was 0.8v. That seemed really low to me.

So far I'm testing 3400-18-20-20 as that seems to boot reliably and already gives a measurable improvement over stock 3000. 3600 at same timings I booted once and it seemed stable in Windows. 3800 I booted once to desktop but totally unstable. I couldn't boot to 3600 again after that.

I'm kinda taking a break from this as the mobo is really horrible to recover from non-boot condition. Even after removing battery, it doesn't start 100% afterwards and goes into some kinda locked state that requires more power cycles to unstick.