Maximum Memory

Whats the max memory that can be installed in Inspiron 1520 running Linux, not windows? Does anybody make a 4 GB stick of DDR2 PC2-5300 • CL=5 • Unbuffered • NON-ECC • DDR2-667 • 1.8V • 128Meg x 64? that would be 1 4GB stick X 2 = 8GB