PC 800 RDRAM running at 400mhz. Is this correct ?

[Duster]

Hi,
What speed should I run my PC800 Samsung RDRAM at.I'm running it at 400mhz at the moment

 

[AndyHui]

That's correct. RDRAM uses a DDR scheme at 400MHz that results in 800MB/s bandwidth.

 

[Mingon]

<< That's correct. RDRAM uses a DDR scheme at 400MHz that results in 800MB/s bandwidth >>




Eh ? 800mb/s ? Do you mean 800mhz or 1.6gb/sec

 

[jcmkk]

Actually PC800 doesn't use a DDR scheme. It uses a dual channel approach. That's why you have to use two sticks. It is just like how the new NForce boards work, but the NForce doesn't force you to use dual channel.

 

[Rand]

<< Actually PC800 doesn't use a DDR scheme. It uses a dual channel approach. That's why you have to use two sticks. It is just like how the new NForce boards work, but the NForce doesn't force you to use dual channel. >>




Actually RDRAM is based upon a DDR scheme, and PC800 RDRAM does indeed run at a nominal clockspeed of 400MHz, which of course equate to the same peak throughput of a theoretical 800MHz SDR RIMM. Mignon is correct however in that the peak theoretical memory bandwidth of a single channel PC800 RDRAM memory subsystem is 1.6GB/s.

Neither DRDRAM as a technology nor the PC800 specification mandates a dual channel memory subsystem, individual chipsets have implemented such but it is not a necessity. The Intel I820 chipset could be used as an emample one DRDRAM chipset in which a single channel RDRAM subsystem is utilized yielding a peak theoretical throughput of 1.6GB/s and naturally as a single channel approach is does not necessitate the installation of RIMM's in pairs.