Ok, here the current status: every works fine.
The dvb support in YaST is probably only useful for basic setups with one card. Take a look at /usr/share/doc/packages/dvb/README.SuSE and create hwcfg-static files manually or put the modules in DVB_LOAD_MODULES (/etc/sysconfig/dvb). This way you can also ensure a load order so your Nova won't suddenly become the primary card.
Ok, this was easy and works good (two hwcft-static files). Thanks!
This morning I had a black TV screen. I got back vdr only after kill -9 vdr13. I will look into this more detailed also today evening. I
did not see
Does your vdr run 24/7?
yes it does. The partly frozen vdr (it still gave messages about events in the log, but the UI was frozen, the screen black) appeard at least twice a day. When I switched to one channel, I got the same problem, UI froze at once (channel info stayed there for 25min). So I disabled all automatic channel info collection, stripped down the channel info to what I really watch. Now vdr is running for 2 days without problem.
Michael