Good! That 512 MB RAM or above 1 GB is better than 512 MB to help more faster than lower.
But 512 MB is cheaper. but 1 GB and 2 GB RAM is kind of expensive. It about 100 to 150 dollars.
For Good to performance on your computer with Windows Vista. System Memory : 512MB RAM, Graphics Memory : Integrated or discrete, Processor modern processor (>800MHz) , Hard Drive >15GB free (recommended), Window Vista Aero Experience : None, Great for... Booting the Operating System, without running applications or games.
For Better Performance: 1GB RAM, 128 MB Graphics Card (integrated or discrete), Processor :1 GHz 32-bit (x86) or 64-bit (x64), 40GB capacity, >15GB free, Aero enabled as a default, but performance may be compromised as more windows, applications and games are opened. Great for Multitasking (e-mail, basic photo editing, basic video editing, music, spreadsheets, browsing, and other applications) The experience is only assured in single monitor mode. Dual monitor is supported, but may affect the aero premium experience.
Best Performance: 2GB Dual Channel, 256MB Graphics Card, Dual-Core, Hard drive, over 50 GB with 7200 RPM. Can enhance Aero experience and system performance. Multi-tasking with power-hungry applications (large spreadsheets, advanced video and photo editing, HD viewing and recording) Dual Monitor Usage.
Excuse me for repeating. I did not ask for it! LOL!