I checked both of my 1721s and this is what is on them:
System image file is "flash:c1700-ipbase-mz.123-6c.bin"
cisco 1721 (MPC860P) processor (revision 0x400) with 55642K/9894K bytes of memory.
I know this model maxes at 128/32, and I don't have that. They are not upgradeable, correct? I should have done better homework before buying them. I have 12.4 Adv IP Services available. Will this run on my two 1721s? If not I suppose they have little real value, because that is all I've got.
If I could go back and do it again I'd just get switches and plug them into the ubuntu box that has a dual core cpu and 6gb of ram and just run GNS3!