XMP is a specific OC setting that is built into the RAM. If you want RAM that will run at 3200Mhz with XMP, then you'll need to buy a 3200Mhz kit of RAM.
Aside from XMP, you can also manually overclock RAM. It is an intensive and long process and not recommended for a novice. But in theory you could run even some 2133MHz kits as fast as 5000Mhz if you very much know what you are doing and are an expert in memory overclocking, like Buildzoid has done.
TL/RD a novice should not be overclocking RAM. Just buy the fastest kit that you can afford and run it at stock settings.