How do you know if speeds are DDR or not

[d4mo]

I couldn't really think of a good way to word this so I will explain better. Most things these days are DDR, so that means they are twice as fast as what they are actually rated at. So my question is how do you know...like when you are shopping newegg, if the thing you are buying is showing the "base number" or the "effective number"(like how an Athlon XP FSB is actually 133 but with the DDR it is 266).

Like I was looking at a few motherboards, and the FSB is listed as 1000mhz HyperTransport. Now I'm pretty sure HT is DDR, so is the FSB 1000mhz, 2000mhz or even 500mhz?

Same with DDR2. Is DDR2-800 actually 400mhz, 800mhz, or 1600mhz?

 

[ForumMaster]

no HT has nothing to do with DDR. you're getting confused.
But in general yes DDR2-800 does run at 800Mhz. DDR PC3200 runs at 400Mhz. DDR2-533 runs at 533Mhz and so on.

 

[Sunner]

Originally posted by: ForumMaster
no HT has nothing to do with DDR. you're getting confused.
But in general yes DDR2-800 does run at 800Mhz. DDR PC3200 runs at 400Mhz. DDR2-533 runs at 533Mhz and so on.

HT is DDR as well.
DDR doesn't refer to DDR memory, it just means "Double Data Rate", which a lot of technologies are/use, HT included.
Anyways, not easy to know just from reading some marketing material since that's intentionally misleading more often than not.
In general if something says "1 GHz DDR" that would be 500 MHz in reality.

There's no "standard" for expressing Single/Double data rates though, so whoever made the paper you're reading made the call.

 

[Roguestar]

http://en.wikipedia.org/wiki/DDR_SDRAM
http://en.wikipedia.org/wiki/DDR2

 

[d4mo]

I wasn't referring to just memory as Sunner mentioned. So how is HT listed usually. ON all the newegg listings for Motherboards with the NForce5 chipset had the FSB listed as 1000mhz FSB. What is the actual speed of that?

 

[Sunner]

Originally posted by: d4mo
I wasn't referring to just memory as Sunner mentioned. So how is HT listed usually. ON all the newegg listings for Motherboards with the NForce5 chipset had the FSB listed as 1000mhz FSB. What is the actual speed of that?

HT speeds tend to be written in their real speeds, kinda unnecessary to write DDR since there's no SDR HT
Anyways, don't confuse "DDR speeds" with actual speed, DDR just means your transmit data on the rising and falling edges of the clock, it's still the same speed.
So that 1 GHz connection is indeed just that, 1 GHz, but it's using DDR signaling, so in marketing speak it would be "2 GHz effective".