Is the AMD Athlon™ II X2 250 an AM3 package processor? Is it backwards compatible?
In addition to AMD’s family of 45nm AMD Phenom™ II processors, this brand new series of AMD Athlon II X2 processors continue to deliver what consumers want by being the industry’s only backwards compatible processors that support both the existing AM2+ infrastructure as well as AM3 platforms featuring DDR3 memory. For those looking to upgrade their platform, AMD can help consumers avoid spending a substantial amount of money when compared to competing desktop platforms that force the additional costs of new memory and motherboard with their processor. AMD allows consumers to customize an upgrade path that’s right for their budget and overall experience they desire.
a second going for a newer architecture. for what you want, an athlon II 620 would go down a treat.
or for a tighter budget, and athlon II 250.
since oyu aren't gaming, you dont need L3 cache, so a phenom II would proabble be a waste of cash.
extra cores would do you very well, especially for the encoding. but if you cant afford that, a dual core 250 would also do very well.