Well, ever since I had the SS4200 it just froze from time to time. I never had a chance to find out the details, because it mostly froze during the day when I was at work, or at night when I was out drin^H^H^H^H studying.
I always thought it was related to my custom kernel. Now it finally froze in my presence, so I could check it out. I opened the case and found the fans spinning rather slowly, and the CPU and northbridge were very hot. I figured the poor thing overheated.
So in fact I was right, because I enabled thermal management and CPU throtteling in my kernel, and loaded all those modules of course.
Add the fact that the Celeron 420 actually doesn't support SpeedStep, and you've got a few kernel moduels going crazy.
I'll remove the thermal and cpu throtteling modules for the time being and see whether that improves stability.
In the long run I want a NAS that doesn't consume more power than really necessary, so I'll probably switch the CPU to a Celeron E1400 or similiar. Those already got a 2nd core and support SpeedStep. While that's got a higher TDP, I think the power consumption is going to be lower, over all.
Guess we'll have to wait and see.