PC Graphics

[Remx]

I installed my new graphics card yesterday, a 7800xt, no worries, the 2 screens connected via HDMI are well recognized and work perfectly.
Today I restarted, the 2nd screen stuck in low resolution.

I decide to connect my main screen with a display port cable, always the same. (the 2nd screen does not have a display port) And when I unplug the first one, it doesn't even start on the second one.
 an idea ?
 THANKS

[opmart]

Same issue on my TV on HDMI port, Resolution is locked at 640X480. When is switch back on old Video card i got 1080P on both Screen