Ram, is it really pc3200 or just pc2700

[ram2]

I keep hearing about manufacturers packaging pc2700 ram as pc3200. Most of the time it is because the ram is running at 200 mhz instead of at 400mhz. I looked in my mainboard manual and saw a schematic showing something about the memory bus being 200mhz, so is this a misconception based on the motherboard, or could this ram really be the lower grade?

I ask this because someone who has the same brand of ram as mine claims his is really pc2700. How could I tell for sure? The system detects it as pc3200, but shows it running at 200mhz.

Thanks

[AsianBatman]

ddr ram runs at 200x2 which = 400.

[ram2]

OK, double data rate, I see. That would mean that pc2700 runs at 2x100 for 200mhz if I understand correctly. If I took out my pc3200 ram and replaced it with pc2700 I would see those speeds listed as 100mhz? I'm using aida32 to see this.

[minibubba]

PC1600 (DDR200) = 100 MHz
PC2100 (DDR266) = 133 MHz
PC2700 (DDR333) = 166 MHz
PC3200 (DDR400) = 200 MHz
PC3500 (DDR433) = 217 MHz
PC3700 (DDR466) = 233 MHz
PC4000 (DDR500) = 250 MHz