Well, it's a little hard to find the CPU support list, but on this site (http://www.overclock.net/t/1331651/question-about-foxconn-2aaf-motherboard-cpus), they pointed to 2 potential Foxconn AM3 motherboards that would be the right chipset, & they seem to have similar (if not identical) lists of supported CPUs (http://www.foxconnsupport.com/cpusupportlist.aspx?type=mb&socket=Socket%20AM3&model=A76ML-K%203.0&cputype=AMD, http://www.foxconnsupport.com/cpusupportlist.aspx?type=mb&socket=Socket%20AM3&model=A76GMV&cputype=AMD).
As pointed out, you're going to be limited to 95W Phenom II CPUs (no FXs allowed). That's the bad news. The good news is, just about any of those Phenom IIs will be a big improvement. Although your current Athlon II X2 215 isn't on Tom's CPU Tier list, from its stats (2.7GHz, 1MB L2 cache) it's right with or right behind the Athlon II X2 240...which is on the tier list, down at 9th-tier (http://www.tomshardware.com/reviews/cpu-hierarchy,4312.html). Now, while the main benefit you'd be looking for in this upgrade is additional cores (plus the access to L3 cache), you'd also want to make sure that your new CPU's cores run at least as fast as the old CPU. At a minimum, you'd want to settle for a Phenom II X4 925; although technically not on the list, that slots in between the 920 & 940, & at 5th-tier that would give you a nice 4-tier jump. If you can, however, I would look for a Phenom II X4 955 (quad-core, 3.2GHz/core, 2MB L2 cache, 6MB L3 cache), which gives you a 4th-tier CPU; just make sure it's the 95W model (HDZ955FBK4DGM), notp the 125W model (HDZ955FBK4DGI). Another good alternative would be the Phenom II X6 1065T (hexa-core, 2.9GHz base/3.4GHz Turbo, 3MB L2 cache, 6MB L3 cache); technically also not on the tier list, but should slot somewhere between the 1055T (5th-tier) & 1075T (4th-tier).