steam on debian wheezy(x86_64) with ATI HD4650, play TF2.

add i386 architecture
#dpkg --add-architecture i386

use "Steam installer for Debian"[1]
#./steam_bootstrap.sh

use LD_DEBUG=libs to check i386 libs
# LD_DEBUG=libs steam

use ATI closed driver[2]

the question of "GL_EXT_texture_sRGB_decode", solved[3]

reference:[1]
               [2]
               [3]