Hello Cisco_Lite,
for example I have:
cisco WS-C6506 (R7000) processor (revision 3.0) with 983008K/65536K bytes of memory.
Processor board ID TBM06402637
SR71000 CPU at 600Mhz, Implementation 0x504, Rev 1.2, 512KB L2 Cache
this is a WS-SUP720-3BXL
modern IOS images are able to autodetect the right size of I/O memory so it should'nt be an issue
note:
in 983008K/65536K bytes the second number is the I/O memory so you can read it from sh ver if it is a Native IOS switch
Hope to help
Giuseppe