I am trying to upgrade my ram from 512 Megs to 1024. The ram I have is 512 DDR PC2700. The manufacturers sticker says that it is 333 MHz but there is another sticker on it that just says 266 MHz. The mother board manual says that the memory slots are DDR 266MHz PC2700 compatible slots. Since the memory already in there is 333MHz I bought 512 more of 333MHz PC 2700 ram but from a different manufacturer. The main question I have is will this be stable? I am assuming that they will both run at 266 MHz because that is what the mobo is rated for, is that correct? Also, does dual channel just mean you have two sticks in 2 memory slots or is that a specific feature that is only available on certain sticks of RAM?

It sure would help to give the motherboard make/model Ram is backwards compatible. PC2700 can run as PC2100 or PC2700...PC3200 can run as PC2100, PC2700, or PC3200. Just make sure to adjust your memory settings in the BIOS correctly. ASUS A7N8X-X Athlon XP 1800+ 8.5 x 200MHz 1024MB PC3200 2.5-3-3-7 Asus A9550GE/TD 128MB WinME/WinXP Pro SP2

Dual Channel RAM is a different animal and your motherboard must support it. 98% of the population is asleep. The other 2% are staring around in complete amazement, abject terror, or both.

Different speed memory chips will typically work together albeit at the lower speed, so in your case that would be 266 MHz. There is a free program that can check the RAM speed for you on your PC, Everest Home Edition system information tool. Download it from........ http://www.webattack.com/downloadfind.php?lc=1&action=s&st=everest&search=Search The question regarding dual channel memory...., if your motherboard supports it then you cannot mix diffrent speed RAM, because the system will NOT run in dual channel mode, and without dual channel the system is considerably slower. I - Sandor J Knowledge is the treasure, but judgment is the treasurer of the wise man. - William Penn (1614 - 1718)