If you need a kick in performance with some additional memory, OCZ has the goods for you.  The 8GB memory kits (4 x 2GB modules) tweaked for the AMD AM2 platform:
Sunnyvale, Calif.—July 23, 2007—OCZ Technology Group, a worldwide leader in innovative, ultra-high performance and high reliability memory, today expanded their memory lineup for AMD enthusiasts and power users with new high-density 8GB “Quad Kits.” The new PC2-5400 Titanium 8GB (4x2GB) Quad Kits were designed exclusively for the AMD AM2 platform and are custom-tailored to the extended column address range of the AM2 memory controller. With a doubled page size, access penalties are reduced to ultimately improve system performance.

OCZ’s newest Titanium AM2 Special kits are optimized to leverage AMD’s sophisticated DDR2 platform for enhanced real world computing experience. With 11 column address bit support by the AM2 memory controller, the number of addresses in each row or page can be as high as 2048 individual entries for a page size of 16kbit. Unlike modules based on standard 10-bit column address chips with an “8k” page size, the new Titanium AM2 Special modules take advantage of the AM2 controller’s feature set and provide a single rank solution with 2GB density using “16k” pages. This allows the controller to stay “in page” twice as long compared to standard memory architectures, thereby achieving unparalleled performance.