Further maximising first RAM OC (Ryzen 7 5700g + g. Skill Ripjaw V 4000 Cl18 2x 32gb)

Hi,
I just build my first PC and I’m currently working on my first (RAM) OC and would love to get some Help/hear some Feedback.

The System is a Ryzen 7 5700g on an ASrock B450 Fatal1ty Gaming-ITX/ac Mobo with 32gb (2×16) of G.Skill Ripjaw V Memory (4000mhz and CL18-22-22-42 1.4V). According to Typhoon it’s Hynix AJR/MJR (So it must be AJR due to being 4000mhz Ram then?)

I was able to get the Frequenzy to 4.133V and set tCL to 17 by raising the voltage to 1.5V. Besides this I just manually set the FCKL accordingly, set Command Rate to 2T and disabled Gear Down Mode.
Ever change downwards in another primary timing lead to faults in hci memtest or not booting at all.

I mainly used [this post](https://reddit.com/r/overclocking/s/0EynkY5k4h) and [this website](https://www.hisevilness.com/articles/technology/overclocking-guide-for-ddr4-ram.html?showall=1&amp=1) as a guide.

Currently I’m stesstesting the Subtimings mentioned in [this comment](https://reddit.com/r/overclocking/s/R60IVUw8f8).

My main problems when researching are:
1. There’s not much info about hynix AJR Dies around
2. I read that the 5700G is different compared to the other 5000 Series chips so I don’t know what SoC to set for example

My Questions:
1. Is there anything important I have overseen in my OC?
2. Is 1.5V VDimm to much?
3. What can I change to make it more stable and get some more primary timings down.
4. What VSoc can I safely try on the 5700G?
5. Is there a database/wiki where I can find things like: “What’s a safeish voltage for a certain part?”, e.g.
6. In the mentioned comment the Values tRDWR,
tWWRD, tRDRDSCL and tWRWRSCL are mentioned, which I couldn’t find in my bios but very similar sounding Values. Are they just called different or is changing thdm just not an option in my bios?