Ok , but it must be a problem with radeon.ko , if I rename it (no radeon anymore), PC can boot , and I have access to console,
With naturaly no xserver .I don't know what to doI stay with siduction 4.15.15 amd64, perhaps debian 4.16.0 amd64 is working.I investigate furter later , it depends on free timeThanks for your help.