Of course yo cannot use A-XMP if you want to use some of the new settings especially with 4 dimms.. I tried upping frequency to 3333mhz with 2 dimms and looser timings, it would not work. With 4 dimms I am still at 2667mhz. The reason I see no change in spite of utilizinmg some relatively obscure settings, is that the 1.72 bios is STILL based on Agesa code 1.04a . I found this out by reading all motherboard data with HWinfo64 a very useful and accurate program. My estimate, only an estimate, is that many of the new settings are not fully functional until the agesa code is update to 1.06 or even the less capable 1.05. I expect more work is to be done and I am glad that this 1.72 beta bios is a step in the right direction.
Let's set just a few things straight...since you're always out for spreading mis-information. I'm quite tired of that at this point.....
1. New BIOS for Tomahawk and Gaming Plus and PC Mate are all based on 1.0.0.6. I know this for a fact.
2. New BIOS for the X370 XPower Titanium is also based on 1.0.0.6. I know this for a fact.
3. There are more and better ways to look into the AGESA version. A version info number in HWINFO64 doesn't really do much anymore, given how many times the OEM's have forgotten to change the version.
All that being said, what more do you want? I'm sorry your RAM isn't working well. If it's that huge of a concern, get better, more supported RAM. Or get a new CPU. Maybe that one will have a better IMC. But things have gotten better for many people. Many are now getting even higher than 3200 MHz, some 3600 MHz and higher.
If it's that huge of a concern to have such fast memory, then find someone who has memory running at 3600+ MHz and get the same memory as them.
Last i checked though, IF doesn't scale much or well after 3000 MHz or so. Granted it was a bit hard to get anything higher than 3200 MHz on most boards, but still. With 1.0.0.6 now, we should be able to see fully how Infinity Fabric scales over frequency. My guess though is that what was true before will still be true, past 3 GHz IF won't scale well.