What Ram does my computer need? DDR? or DDR2? and what is the max i can install, thanks. Its an old comp 
Processor
2.40 gigahertz Intel Celeron
16 kilobyte primary memory cache
256 kilobyte secondary memory cache
Main Circuit Board
Board: MICRO-STAR INTERNATIONAL CO., LTD P4M266-8235
Bus Clock: 133 megahertz
BIOS: Phoenix Technologies, LTD 6.00 PG 12/23/2004
Memory Modules
480 Megabytes Installed Memory
Slot 'A0' has 512 MB
Slot 'A1' is Empty
Slot 'A2' is Empty
Processor
2.40 gigahertz Intel Celeron
16 kilobyte primary memory cache
256 kilobyte secondary memory cache
Main Circuit Board
Board: MICRO-STAR INTERNATIONAL CO., LTD P4M266-8235
Bus Clock: 133 megahertz
BIOS: Phoenix Technologies, LTD 6.00 PG 12/23/2004
Memory Modules
480 Megabytes Installed Memory
Slot 'A0' has 512 MB
Slot 'A1' is Empty
Slot 'A2' is Empty