This question is similar to the following: But asking the broad question of who to believe when seeking memory upgrades?
An MSI-7309 (K9N6SGM-v) Has (2) slots to fill. I am not exactly sure of the capacity. Included below are links to conflicting specs. I know that it can hold at least 2 Gigabytes. I would like to get 4GB in there. Without having to pay for return shipping or a restocking fee.
MSI manual - www.msi.com/product/mb/K9N6SGM-V---K9N6PGM-FI---K9N6PGM-F.html#/?div=Manual
Newegg - www.newegg.com/Product/Product.aspx?Item=N82E16813130068
Memory X - memoryx.com/msi-k9n6sgm-v-ddr2-800mhz-ram-memory-upgrade.php
Tiger Direct - www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=3876566&CatId=2323
Kingston - www.ec.kingston.com/ecom/configurator_new/modelsinfo.asp?SysID=35818&mfr=MSI&model=Motherboard+K9N6SGM&search_type=&root=us&LinkBack=http%3A%2F%2Fwww.kingston.com&Sys=35818-MSI-Motherboard+K9N6SGM-V&distributor=0&submit1=Search
MSI - www.msi.com/product/mb/K9N6SGM-V---K9N6PGM-FI---K9N6PGM-F.html#/?div=Detail
Crucial - crucial.com/store/listparts.aspx?model=MS-7309%20%28K9N6SGM-V%29&Cat=RAM
C-Net reviews - reviews.cnet.com/motherboards/msi-k9n6sgm-v-motherboard/1707-3049_7-32149344.html