What RAM Memory i need for HP EliteBook 8440p? i have only 2 GB RAM in it an i would update to 4 GB RAM. Thank you for...

Memory Two customer-accessible/upgradable memory module slots 333Supports dual-channel memory 333DDR3 PC3-10600 1333-MHz memorySupports the following configurations: ■8192-MB total system memory (4096 x 2) ■4096-MB total system memory (4096 x 1) ■4096-MB total system memory (2048 x 2)* ■3072-MB total system memory (2048 + 1024)* ■2048-MB total system memory (2048 x 1)* ■2048-MB total system memory (1024 x 2)* ■1024-MB total system memory (1024 x 1)**Brazil 1333-MHz memory configuration