I don't know a lot about what's important with memory compatibility.  

I have an Epox AMD mobo with...

Corsair  Dual Channel Kit Desktop Memory
XMS  
TWINX1024-3100C2
184-Pin DDR SDRAM

1GB (2x512MB) 
CAS Latency 2
Timing 2-3-3-6
No ECC
Unbuffered
Heat Spreader

I have two free slots.   Can I safely insert this memory...??
http://tinyurl.com/2ty3hr  (newegg)

Corsair  Dual Channel Kit Desktop Memory
XMS2
TWIN2x2048-6400C4
240-Pin DDR2 SDRAM DDR2 800 (PC2 6400)

2GB (2x1GB)
Cas Latency 4
Timing 4-4-4-12
2.1V
Heat Spreader
SLI certified (my mobo has sli, but I thought that was for video?)
High Perform/Gaming
 
If I just insert this (or othe) memory into the mobo, do I have to do anything else?  
Do I have to do anything about making sure the two pairs work as pairs?

Thank you,
AnnaSummers

              The NOSPIN Group is now offering Free PC Tech
                     support at our newest website:
                          http://freepctech.com