Please help for upgrade!

So i was about to put my new Crucial m4 SSD into my pc today, and realized that my pc only has SATA 3 3Gb/s connector. So i'm thinking of upgrading my motherboard, 1 so my ssd can go as fast as possible and 2 because my other 1 ( Gigabyte GA-MA770T-UD3 ) is quite old! 

Please some suggestions for a am3 motherboard that is quite decent, and I don't want to go much over £100...

PC Specs :

CPU- AMD Phenom II X4 955 3.20Ghz
Motherboard - Gigabyte GA-MA770T-UD3
RAM - 4GB Kingston 1333Mhz
GPU - MSI Twin Frozr III R7870 OC Edition
PSU - Corsair CX600
SSD - Crucial M4 64GB
HDD - 160GB 7200Rpm, don't know make or anything!  

thanks in advance