i still have this problem after i've done this think

prsn i can use the mat_dxlevel81 command?

Thx guys for being here to help
So i cant provide with specs beacuse im not in my pc right now
butt my launch options are -dxlevel81 -w1280 -h768
And i tried to do this without cfg but i didnt work.

So when i paly tf2 the first match is fine but when the game loads the second match the screen goes black and gets me out of the game.Then i can open tf2 and play the rest of the match fine and the same think happens when i load the 3rd match the screen goes black and gets me out.My config is this
mat_phong 0
bind k kill

bind o "say I'm using a bind to apologize for a random crit that I didn't deserve to get.Sorry"

fov_desired 90
cl_interp 0
hud_combattext_batching 1

mat_shadowstate 0
r_shadowmaxrendered 0
r_shadowrendertotexture 0
r_shadows 0

cl_ragdoll_fade_time 0
cl_ragdoll_forcefade 1
cl_ragdoll_physics_enable 0
g_ragdoll_fadespeed 0
g_ragdoll_lvfadespeed 0
ragdoll_sleepaftertime 0

cl_phys_props_enable 0
cl_phys_props_max 0
props_break_max_pieces 0
r_propsmaxdist 1
violence_agibs 0
violence_hgibs 0