(Please speak in english as we are not in the international part of the forum.)
Have you updated your graphics drivers as [Unknown] told you earlier ?
If yes, and nothing changes, you can try to switch GPU backend directly in the config file, given that you can't use the UI :
Close PPSSPP, then go to "\memstick\PSP\SYSTEM", open the "ppsspp.ini" file, find the "GPUBackend = 0" line and edit it to "GPUBackend = 1".
Have you updated your graphics drivers as [Unknown] told you earlier ?
If yes, and nothing changes, you can try to switch GPU backend directly in the config file, given that you can't use the UI :
Close PPSSPP, then go to "\memstick\PSP\SYSTEM", open the "ppsspp.ini" file, find the "GPUBackend = 0" line and edit it to "GPUBackend = 1".
♦ Intel Core i7-6700HQ | 16 GB RAM | NVIDIA GeForce GTX 960M | Debian Testing
♦ Intel Core i7-2630QM | 4 GB RAM | NVIDIA GeForce GT 540M | Debian Testing
♦ PSP-3004 | 6.60 PRO-C2
♦ Intel Core i7-2630QM | 4 GB RAM | NVIDIA GeForce GT 540M | Debian Testing
♦ PSP-3004 | 6.60 PRO-C2