I'll start with the pictures:
Thoughts and implications for the SFF world:
WTF is up with the fan placement?
The fan in line with the PCB doesn't seem like a good idea with sandwich cases, maybe better for temps in Ncase type cases?
End mounted power connectors adds additional length
280 mm...
Notes:
Active VRM fan :(
19 pin type e header
Up to DDR4 5100 Mhz
"8+2 DrMOS voltage regulator module"
Intel I225-V 2.5Gb Ethernet
1 x gen 4 m.2, 1x gen 3 m.2
1x pump, 3x fan headers
1x thunderbolt 3 internal header
Price: $229
EDIT: The webpage is up: https://www.asrock.com/mb/AMD/B550 Phantom Gaming-ITXax/index.asp
Interesting things:
USB C 19 pin type e header (!!)
No riser or chipset fan
Looks like 3 + 1 fan headers
1x front gen 4 m.2
1x rear gen 3 m.2 slot
2.5 gig ethernet
"8 Power Phase Design, Digi Power, 90A...
Asrock has 2 itx models for Z490: The Z490M-ITX / AC and the Z490 Phantom Gaming-ITX/TB3.
Interesting things:
The Z490M-itx has 2 top m.2 slots
The phantom gaming has a gem fan, also a riser for connectivity.
Neither has a type e 19 pin header :(