The M4A88TD-V EVO/USB3 is an AM3 board whilst the M5A88-V EVO is a AM3+ board.
Difference Between AM3+ and AM3 Socket
- Socket AM3+ socket has an extra pin ( unused ? - citation needed)
- The AM3+ motherboard will have bigger hole. This increased the current carrying capacity and eases processor insertion into the motherboard.
- The bigger hole also increase the signal integrity as has been claimed.
- The clips to hold the fans have improved design that will make the CPU cooler.
- AM3+ sockets are backward compatible with the AM3 sockets. -The latest Bulldozer processors require AM3+ socket, but a AM3 socket may also work with BIOS upgrade. Check with motherboard manufacturer.
Overall the AM3+ is the better board in upgrade terms.