B850M-X [WiFi] quick review.

Finally built an AM5 system, after building 10 AM4 systems, all AsRock.
I go for AsRock for their ECC memory support.

* B850M-X WiFi
* Ryzen 7 9800X3D with Noctua NH-D12L
* Micron MTC20C2085S1EC56BR (ECC Unbuffered 5600MT/s 46-45-45-90)
* Micron MTC20C2085S1EC56BR (ECC Unbuffered 5600MT/s 46-45-45-90)
* NVMe0: SK Hynix Platinum P41 2TB
* NVMe1: SK Hynix Gold P31 1TB
* SATA0: Samsung 850 PRO 1TB
* SATA1: Samsung 850 PRO 1TB
* SATA2: LG WH14NS40 BD-RW (flashed to WH16NS60 1.03 Mk)
* SATA3: LG WH14NS40 BD-RW (flashed to WH16NS60 1.03 Mk)
* No dGPU at the moment.
* One Intel i210 PCIe ethernet card.
* Seasonic PRIME PX-500 (Fanless)
* MediaTek MT7922 WiFi card replaced with Intel AX210NGW

Some interesting notes about B850M-X and B850M-X WiFi.

* It's the only non-mini-ITX board with just two DIMM slots. I consider four DIMM slots useless on AM5, except for in niche use cases. The ratio of 4-DIMM to 2-DIMM motherboard is inverted in my opinion, but I bet normies flock to 4-DIMM boards anyway. 64GB DDR5 DIMMs just started to show up in the market, so we can get 128GB with just two DIMM slots. No need to reduce speed/reliability with 4 DIMMs.
* It's unlike all other AsRock B850 (and maybe B870) micro-ATX models, in that both m.2 NVMe slots are connected directly to the CPU. All their other motherboards route 4 CPU-direct PCIe lanes to the 2nd PCIe x4 slot. This can be more flexible, since you can always use an m.2 NVMe PCIe adapter, whereas the other direction is a lot more complicated. But for my use, I like both NVMe slots being connected directly to the CPU.

A couple of complaints.

* What's up with the cheap Realtek ALC897? Give me ALC1220 or ALC1200 and charge $10 more. Heck, I'd have paid $20 more for it.
* MediaTek MT7922 (AMD RZ616) is probably fine, but I wish they'd give you the option to choose. Yes, I could've bought a non-WiFi version, but it doesn't come with the antenna connectors, so I chose to get the WiFi version and replace the WiFi card. It was only $10 difference, though, plus $20 for the AX210, of course.

All in all, pretty unusual board for a great price.

Last note: Some people might feel uneasy with 6+1+1 VRM, maybe with 9950X or something. It's probably fine for most uses, though. I never enable boost on any of my CPUs, so it's not an issue for me. Heck, I'm running in ECO mode (65W TDP, 88W PPT). I might be the only person in the world who runs 9800X3D in that setting, without dGPU and with ECC memory. What's crazy is that the 9800X3D's base clock is way higher than 5800X3D's boost clock. Big generational difference.