Is it true that the DDR2 800 has a maximum real clock of 400 MHZ?

Answer 1

Yes that is true. I wasn't going to go into the technicalities of it, but since the last guy tried (and failed) I suppose its a good idea to get the right info out there. DDR stands for double data rate. This means that on each clock cycle, two pieces of data are sent instead of one. So while the real clock is at 400Mhz, the effective rate is 800Mhz. This is true on both DDR and DDR2, and DDR3 RAM for that matter. The 2 and 3 just refer to the generation of the RAM, all however are double data rate and will have a real clock speed of one half its listed effective clock speed.

Answer 2

With DDR2 ram, the ram always runs at half of the listed clock speed. But it makes up by being able to use both banks of the memory (the 2 in DDR2). So a DDR2 800 would actually be running 2 DDR 400s.

Answer 3

YES, unless you overclock.

Answer 4

TRUE