Ethernet connection for cisco 2600xm

my company is setting up a co-loacation for production machine. the co-location consist of 4 servers. one will function as SQL server, one is going to be primery web server and the other 2 are web/mail servers. the ISP is going to dedicate 1MB Ethernet bandwidth for starter. we have cisco2620XM. we have to connect to thirer to
thier router. the Eitehrnet card I found was the NM-1E but according to cisco spec that card operate at 10 base T. the question is will that be enough?