How can I allocate more than 1024 MB of RAM to an Android Virtual Device?
In the 'Create new Android Virtual Device' window in Eclipse it says, "On Windows, emulating RAM greater than 768M may fail depending on the system load. Try progressively smaller values of RAM if the emulator fails to launch."

As answered here https://stackoverflow.com/questions/8853541/why-cant-i-boot-an-avd-from-eclipse-with-1024-mb-of-ram, there is a .ini file you can edit in [username]\.android\avd[avd name.avd]\config.ini that you can edit by changing 'hw.ramSize=1024' to 'hw.ramSize=1024MB'. I tried it and it worked for me.