I has a question, please tell me!
I can change vram from pic 2 to pic 1. Pic 1 has one error ( check X )
Pic 1: gtx1080 8gb (vram: 6VA77 - D9TXS)
Pic 2: zotac p104-100 4gb ( VRAM: 7WA77 - D9VRL)
Thank a lot!

yes, you can change this.
this memory bank something different and they have different speed, but it permissible replacement.
D9VRL - GDDR5X SGRAM,8G(256Mx32bit),0.727ns,FBGA-190pin,MICRON/MT58K256M321JA-110:A,1.3095V,1.3905V
D9TXS - GDDR5X SGRAM,8G(256Mx32bit),0.8ns, FBGA-190pin,MICRON/MT58K256M32JA-100:A,1.3095V,1.3905V

during overclocking, at maximum frequencies, nuances may arise, but personally I have not seen this.

It not working, sir!
Maybe it different