• Supports two unbuffered DIMM of 1.8 Volt DDR2 SDRAM
• Supports dual channel DDR2 memory architecture.
• Supports DDR2 400/533/667 memory interface. (4GB Max)
But I am not sure if I understand what the specification means.
That's clock speed, multiply by 8 to give your PC rating, eg. 400 * 8 = PC3200, 533 * 8 = PC4200, 667 * 8 = PC5300
They round down to the nearest 100, (for DDR2 anyway).