Thanks so far. Someone else thought it's from sparklepower, so I just sent them an email. Let's hope they'll answer and it's one of theirs.
If it's really 350W I'd like to use them for new 12-Core Opteron Systems (1x Opteron 6344, 8x16GB RAM, 2x3TB HDD, 2x500GB SSD). 350W should be more than enough, for this right?