Most of those oem motherboards only work with cpus rated up to 95 watts. If you try one of the phenom II's rated at 125 watts, they probably won't work. There are some Phenom II's rated at 95 watts. They may work, but there's no guarantee. If your motherboard uses ddr3 ram, they odds are in your favor. Older ddr2 boards are less likely to work with newer cpus with oem systems. To sumarize, oem systems by dell, packard bell, acer, etc aren't designed to upgrade the cpus. Bios updates are sometimes available, but if you're not experienced flashing the bios, you could end up with a dead board. You must also know that your original windows installation is tied to the original motherboard by a small bios file. Changing boards may cause your windows installation to fail to load. So, if you still want to upgrade the cpu, be prepared to change to another micro atx board and purchase a new windows coa if required. The cost of these may not be worth it.