Huge memory consumption on Radeon 7800 series comparing to 6970 when handling non power of 2 textures.
I need to use many non power of 2 textures as I work with live streams and videos textures. I have problem
problem with a huge memory consumption on Radeon 7800 series cards (checked on 7850 and 7870) especially when using Full-HD video textures. After comparing it with 6970 I'm sure that 7800s handle mipmaping on non power of 2 textures completely different than 6900s.
On 7800s textures are extended to power of 2 dimension and then creates mipmaps while on 6970 mipmaps are created till one of dimension is odd and they are not extended. Without mipmapping my GPU memory usage is identical on 6970 and 7870 and it's about 900MB-1GB.
After turning mipmaps on its 1.3GB on 6970 and 1.9GB on 7870! Is there any hidden option (maybe in registry) to turn off filling textures to power of 2 before mipmaping?
I also checked on GF 480 and it's consumption is similar to 6970.