Pc3200 = Pc400?

I need to know if I have my info straight or if I'm stupid. This is what I believe...
PC66 = 66 Mhz SDRam
PC100 = 100 Mhz SDRam
PC133 = 133 Mhz SDRam
PC400 = 100 Mhz RDRam (200 x 2)
PC600 = 100 Mhz RDRam (300 x 2)
PC800 = 100 Mhz RDRam (400 x 2)
PC1066 = 133 Mhz RDRam (533 x 2)
PC1600 = 100 Mhz DDR-SDRam (DDR 200)
PC2100 = 133 Mhz DDR-SDRam (DDR 266)
PC2700 = 166 Mhz DDR-SDRam (DDR 333)
PC3200 = 200 Mhz DDR-SDRam (DDR 400)
PC4200 = 133 Mhz RDRam (533 x 1) (Also called RIMM4200, this is the 32-bit modules)
PC3200 is also know as DDR400, Not PC400. Thoses are 2 different things right? The reason I ask is because I bought some PC3200 off somebody on ebay and they sent me PC400, telling me they are the same thing. The memory won't work in my system and I can't get it into his head that they are 2 different types of memory. Thanks for your response.
:confused

 

From "The Memory FAQ" we get this:

"The speed of DDR is usually expressed in terms of its "effective data rate", which is twice its actual clock speed. PC3200 memory, or DDR400, or 400 MHz DDR, is not running at 400 MHz, it is running at 200 MHz. The fact that it accomplishes two data transfers per clock cycle gives it nearly the same bandwidth as SDRAM running at 400 MHz, but DDR400 is indeed still running at 200 MHz.

Actual clock speed/effective transfer rate => specification

100/200 MHz => DDR200 or PC1600
133/266 MHz => DDR266 or PC2100
166/333 MHz => DDR333 or PC2700
185/370 MHz => DDR370 or PC3000
200/400 MHz => DDR400 or PC3200
217/433 MHz => DDR433 or PC3500
233/466 MHz => DDR466 or PC3700
250/500 MHz => DDR500 or PC4000
267/533 MHz => DDR533 or PC4200
283/566 MHz => DDR566 or PC4500"

http://forums.pcper.com/showthread.php?t=320351

Hopefully that will clear it up for you.

Sounds like someone maybe trying to pull a fast one on you, here this explains it even better and they cant argue with this:

http://en.wikipedia.org/wiki/DDR_SDRAM

Make them read that and tell them not to be deceptive or you will be forced to take what ever legal options you have!

 

Strangely PC400 shouldn't even be able to fit into the memory module slots!