Dual Channel DDR as fast as PC1066 RDRAM?

[christoph83]

Has anyone to this date effectivly released a dual channel DDR chipset? Intel is releasing their granite bay chipset sometime this summer around the time 533FSB RDRAM boards will come about. Both of these motherboards theoretically support 4.2gb/s. And if we talk PC2700 Speeds and PC1200 RDRAM were talking 5+ gb/s for both of these guys. I'm curious though because when both of these come out, if the dual channel DDR does what its theoretically sopposed to do, wont it be just as fast as an RDRAM setup?Or am I missing something here. I know the latencies get higher as you overclock DDR which is the opposite for RDRAM but wont they both be around the same area in latencies? All we seem to be hearing about is how fast RDRAM is at PC1066. Well what about dual channel DDR? Any information is appreciated.

 

[AGodspeed]

<< Has anyone to this date effectivly released a dual channel DDR chipset? Intel is releasing their granite bay chipset sometime this summer around the time 533FSB RDRAM boards will come about. Both of these motherboards theoretically support 4.2gb/s. And if we talk PC2700 Speeds and PC1200 RDRAM were talking 5+ gb/s for both of these guys. I'm curious though because when both of these come out, if the dual channel DDR does what its theoretically sopposed to do, wont it be just as fast as an RDRAM setup?Or am I missing something here. I know the latencies get higher as you overclock DDR which is the opposite for RDRAM but wont they both be around the same area in latencies? All we seem to be hearing about is how fast RDRAM is at PC1066. Well what about dual channel DDR? Any information is appreciated. >>

The only dual channel DDR chipset to date is the nVidia nForce 220/420 chipset (Socket A), providing 4.2GB of bandwidth using PC2100 DDR DRAM. All other DDR chipsets on the market (Socket A and Socket 478 boards) are single channel solutions.

The only desktop-level Rambus chipset to date is the Intel i850 chipset, providing 3.2GB of bandwidth using PC800 RDRAM using dual channel technology. The only reasons I've heard that RDRAM must be used in a dual channel configuration is due to a single channel setup latency penalty. Theoretically, a dual channel RDRAM setup halves the latency penalty and doubles bandwidth. A DDR dual channel chipset halfs latency and doubles bandwidth too.

Here's a general overview of DDR and RDRAM:

PC1600 DDR DRAM: Theoretical 1.6GB bandwidth
PC2100 DDR DRAM: Theoretical 2.1GB bandwidth

PC800 RDRAM: Theoretical 1.6GB bandwidth

 

[christoph83]

Ok thanks for the info. So what im getting at here is in 6 months how is PC1066 RDRAM going to make a difference between a dual channel DDR setup with plain PC2100 DDR. Theoretically they will be the same speed.

 

[Bozo Galora]

IDF : Rambus RIMM 4200
Rambus will demonstrate RIMM(TM) 4200, the world's highest bandwidth- PC memory module. The RIMM 4200
module integrates two RDRAM memory channels to deliver 4.2GB/s of memory bandwidth from a single module.
Using standard RDRAM components, RIMM 4200 modules operate with existing RDRAM controllers, and enable
single module upgrades of dual channel memory systems. Furthermore, with built-in channel termination, RIMM
4200 modules simplify motherboard design and require less than 5 square inches of system board area. The
demonstration system to be shown at Intel Developer Forum uses a low cost four-layer motherboard and
modules that fit in standard memory connector footprints using a 232 pin version of the RIMM connector. In
addition to the system demonstration of RIMM 4200 modules, Rambus will also be demonstrating 1200MHz
RDRAM operation in a PC.