so which is faster, ddram or rdram?

[gopunk]

i know theoretically rdram is supposed to be faster, but i thought i heard something about latency problems. then i heard they used dual controller mbs to cut those in half, but then the nforce uses those too... so after everything, which is faster?

 

[TunaBoo]

Depends on too much stuff.

But rambus is

a) a piece of trash company
b) overpriced
c) not going to be around long.


Go for DDR... but there is never really a choice of DDR or RAMBUS. If you want p4, right now u are stuck with Rambust. If you want athlon, you got DDR or SDRAM.



It is like comparing apples to electrical tape.

 

[zephyrprime]

Hmmmm, you're right. I've never seen a real head to head comparison between ddr and rdram because the P4 doesn't support ddr and the Athlon doesn't support DDR. It'll be interesting to see some tests when the P4 gets ddr support.

 

[NelsonMuntz]

DDR has a higher transfer rate and a lower latency than RDRAM in a single channel configuration. The Intel 850 chipset gives dual RDRAM channels to give greater bandwidth than DDR in a single channel conficuration, but as you mentioned nForce is a dual channel DDR solution which provides a larger bandwidth than RDRAM and it still has the lower latencies, so it should easily beat the RDRAM.

 

[gopunk]

thanks guys

tunaboo: yea i'm not shopping around, i already got ddr because of price but i was just curious. one of those things where i thought i knew the answer at one point but was just confused.

zephyr: yea, there's just too many factors to compare them properly i guess. i mean even if you get the same type of ram, you still have different chipsets for mbs.

nelson: thanks, that was the validation i was looking for.

 

[AndyHui]

Latency is not that much of a factor on the i850 chipset. The chipset has been designed to hide the latencies involved with RAMBUS, as well as the P4 support data prefetch....again minimising the RAMBUS latency.

The Pentium III was hit really badly by the latency, since the i820 and i840 chipsets were not designed to hide the associated latency problem, nor does the Coppermine support data prefetch.

 

[gopunk]

andy - so if the i850 was better on latency and it's dual controller, is theoretically a bunch faster than ddr (and what about after nforce comes out)? i didn't know they alleviated the latency issue, i thought they just did the dual controller thing.

 

[AndyHui]

Well, the i850 is a dual channel RDRAM controller. In this configuration it handily beats a single channel DDR chipset: the i845-D (Brookdale DDR) chipset for the Pentium 4 is still not going to beat the raw performance of the i850.

The nForce supports dual channel DDR. Depending on how well nVidia implements the memory controller, combined with the additional 1GB of bandwidth, this solution should give better performance than the i850 chipset.

 

[ToBeMe]

Simple answer......RDRAM is technicly (sp) the best there is right now. Rambus the company, and since it's closed source, make it much less attractive to everyone! RDRAM is NOT going away.....it will always be around and serve "niche" applications. The next steps in RDRAM, just as the next steps in DDRRAM will make it much faster! PC1600 & PC3300 will blow even the best advances DDR has away according to prelim. B/M's! Just run any memory B/M's and it is very clear that RDRAM is far superior and if the company would get it's head out of it's arse and open it up which in turn would lower prices, RDRAM WOULD become the norm.........this isn't going to happen, so, we'll never see that IMHO. For my PIV's though, it will always be RDRAM!