OK, I have matched up the output from cat /proc/pci to my stack of manuals and come to the comclusion that the server is using a Asus P2B-L motherboard or a very close sibling. It sports 4 DIMM sockets, of which 2 are currently taken by 128Mb modules (97% sure). The slots accept "Intel PC100-compliant SDRAMs (8, 16, 32, 64, 128 or 256Mb) up to 1024Mb", according to the manual.
I want to stress 2 things.I would really, really appreciate this. And I would use every megabyte for more games, which I think is something like 1 game/4Mb, though I would increase the limit gradually. But I want this to be 100% voluntary. In a few months the server will probably be upgraded in any case. I would say ETA is between 2 and 6 months.
If you decide to go ahead and do this, the address is, (transmogriffed to international mode
Esben Mose Hansen
Blomstermarken 2
DK-3450 Alleroed
Denmark