I'm running 8 GB of DDR3 1600 RAM =) gotta love having full use of it!
B keep in mind if you install 64 bit, any hardware or software that isn't 64 bit capable may or may not work.
I have a external Linksys USB wireless adapter, linksys like soundblaster shits on its customers with any driver updates. Thankfully 328409820394823 people bitched about it and while linksys said to just buy a new device, someone else said F that and made drivers.
Look into your recording software, make sure it supports 64 bit.
So far most of my stuff is 64 bit, however a few of my things are not and the best I have is TBA on drivers. I've found ways of tricking the programs to work but IMO it takes too much work to make it worth while. For melodyne, you must change your audio settings in sonar, keeping in mind that will change my keyboard/samples and cause major delay, however the Melodyne plugin will work, once you're done using it you record it to a track, save, then reset your settings back..... Not worth it.
Sonar check
Motu interface check
Komplete check
Kontakt check
Battery 3 check
Guitar Rig 4 check
Pretty much anything NI check
EZ Drummer = Fial
Melodyne = Fial
Dummer Session check
Thankfully most places offer 64 bit install files.