---------------------------------------------------------------------------------------------You are running it in dual mode if it says Dual Channel, Linear, 400. I have a 533mhz bus processor with my memory running in dual 333 mode. For me it says: "Dual Channel, Linear, 333". That POST screen is the only place I could find that says anything relating to the status of your memory being in single or dual mode. It does go by a bit too quickly unfortunately. You should run some benchmarks (SiSoft Sandra's memory bandwidth test). That will give you a good idea of the actual bandwidth your memory is capable of. It will give you relative benchmarks of other similar setups to compare to. It should be fairly obvious if you're running in single or dual mode when you see your results compared to the others listed.
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Thanks for the replies everyone. I downloaded a copy of cpu-z. Before I got around to using it I hit f5 to reset my bios defaults. For some reason this caused the dual channel message to come up and I have had it ever since, even after altering my bios settings manually again.
Regarding the initial startup of the system. I did not take out the battery to reset my bios when I got my board. I just went into my bios and made sure everything was set as standard as possible and that nothing was overclocked, set for turbo, or set for auto if there was a standard option. Then I went from 1005 to 1006, 1007, 1008 bios versions. Sometimes when I did a flash and restarted it would give a bad check sum or overclock failed. If I got the bad check sum I would just cold boot a couple of times and it would come back up correctly. If I got the overclock failed, it generally meant the the new flash had reverted some bios settings to something that wouldn't work on first boot (like setting a standard back to auto or turbo...). So I would just go back into the bios and reset things back to standard. This always worked for me. Once you get things up and going and have flashed your bios, it seems to take bios changes better and only gives overclock failed if you really push something out of whack by overclocking too far.