What is this V9990 board

I think it's an evaluation board, as seems to indicate the Japanese description :

(Excite translation)

I send the board by which VDP of YAMAHA V9990 is carried.
RAM for a Z80 compound chip and VDP, etc. can be checked.
However, whether it operates normally has the unknown parts carried.
Checking of operations is not carried out at all.
(There is not an EPROM.)
It did not utilize, although awarded as an object for research at this auction before.
I need your help by a no claim no return.
I ship in the letter pack 500 from Hyogo Prefecture.
It restricts to the letter pack 500 and is mailing cost no charge.
When a Yu-pack is wished, I pay 500 yen here.

See also :
http://www.ctv.es/USERS/hnostar/TECH/GFX9000/gfx-2.htm

is not the Yamaha V9990 evaluation board , i see it at home friend in past , it's smaller