well, I checked msi's website very thoroughly when I bought the fx 55 last year (or so I thought), but I went ahead and did some more research this time. Come to find out, I can get an opteron 180 or an x2 4800 toledo. see info here:
http://global.msi.com.tw/index...=165&maincat_no=1#menu
I could even use an fx 60 so I'm assuming that an opteron 185 would be fine, too. new egg has an opteron 185 for $249 or I could go budget and get an x2 4400 for $139.
I don't really want to buy a new system quite yet since I am holding out for nehalem, or, barrying that, at least penryn/barcelona. I don't play oblivion or anything that caused the old processor any problems, so I can probably hold out for a while if everything holds up.
Of course, I could just hold out until july 22, buy a q6600 for 266, a kandalf for 280, etc...