Dell Inspiron 6400 Memory Upgrade to 4GB.

Below is my brief system summary. I have 1GB (2x512 MB) RAM right now. I want to upgrade to 4GB of RAM. As per previous posts I can see that it is recommended but I want to know if I can upgrade to 2x2GB PC6400 DDR2 800MHz RAM (right now I have 2x512MB DDR2-533 SDRAM). Kindly suggest.

  Processor Summary
     Processor:                Intel Core Duo T5300 1733 MHz

  Motherboard Summary
     System Name:              Dell Inc. MM061
     Motherboard OEM:          Dell Computer Corporation
     Board Model:              Dell Inc. 0KD882
     BIOS Version:             Phoenix ROM BIOS PLUS Version 1.10 A17 for Dell
     Chipset Vendor:           Intel Corporation
     Chipset:                  Mobile Memory Controller Hub
     Southbridge Vendor:       Intel Corporation
     Southbridge:              82801GBM (ICH7-M) LPC Interface Controller
     DMI/SMBIOS Version:       2.4

  Memory Summary
     Memory Size:              1038712 kB (1014.37 MB)
     System Memory:            1016 MB
     1st Memory Module:        512MB DDR2-533 SDRAM (Unknown (7F7F7F7F7F51h))
     2nd Memory Module:        512MB DDR2-533 SDRAM (Unknown (7F7F7F7F7F51h))

  Video Summary
     Monitor Vendor:           LG Philips
     Monitor Model:            Unknown (LPL A900)
     Video Chip Vendor:        Intel Corporation
     Video Chip:               Mobile Integrated Graphics Controller
     Video Memory:             224 MB

  Sound Summary
     Sound Chip Vendor:        Intel Corporation
     Sound Chip:               82801G (ICH7 Family) High Definition Audio