When installing DIMMs, try to evenly divide the amount of RAM available between the two ports.
For example, if you have 12 DIMMs (eight 512 MB DIMMs and four 1 GB DIMMs for a total of 8 GB), install all eight 512 MB DIMMs (4 GB) in one port and the four 1 GB DIMMs (also 4 GB) in the other port. This will give you better performance than mixing four 512 MB DIMMs and four 1 GB DIMMs (6 GB total) in one port and four 512 MB DIMMs (2 GB) in the other port.
Additional memory considerations
An x440 system with two SMP Expansion Modules installed currently supports a maximum of 64 GB of memory, using 2 GB DIMMs. To enable your operating system to address this amount of memory, there may be certain operating system configuration modifications required.
For example, to enable Windows 2000 Advanced Server and Datacenter Server to access physical memory over 4 GB, the /PAE switch is required in the boot.ini file. For detailed information on the /PAE switch and the /3GB switch, refer to Microsoft Knowledge Base Article Q283037 at:
3.1.3 PCI slot configuration
As shown in Figure
These six slots are implemented using four PCI buses, labeled
Bus A (slot 1 and slot 2): Two
Bus B (slot 3 and slot 4): Two
Bus C (slot 5): One
Bus D (slot 6): One
