Is DDR Memory Any Good for CPU's Other Than

[MegalosSkylaki]

AMD/XP, P3(Tualitin ONLY), and P4 ?

Is it's bandwidth and speed wasted on a:

-- Thunderbird Athlon
-- NON-Tualatin P3
-- (Socket 423 P-4)
-- Others: Duron, Morgan Duron, Celeron non-T, Celeron T

DOOOOOOOG

[Bob The Great]

No it's not. Infact if any thing it's not fast enough.

Sdram is getting to slow IMO. Initially DDR and Sdram in certain cases preformed about the same with DDR pulling ahead some. But now, and espiecially in the future it appears DDR is going to be the way! The Clawhammer shows just how powerfull that mem can be with a good cpu behind it!

[squeech]

There's an age-old saying about how computers sometimes tend to run into trouble when the memory clock runs faster than the frontside bus. This is not always true, but in many cases performance can lag.

My answer to your question is no. The bandwidth is not wasted on any of the above listed processors. However, for example, you may want to only run DDR200 with a processor running at 200MHz FSB for optimum performance; thus ruling out a few combinations.

You would still see an increase in performance over SDRAM, however some motherboards with soft BIOS settings for the clock speeds do not like it when memory exceeds the CPU.

However, my tech rig at work is a Duron 900 with 256MB of DDR266, when the Duron is a 200MHz FSB processor. But my motherboard allows for all the clock settings to be done with DIP switches and jumpers.

But all that aside, in direct answer to your question, all of the processors listed, in my opinion, would only have performance to gain from pairing them up with DDR RAM. Just beware of how the motherboard is able to handle the two (FSB and memory).

[Whir]

Nah, I would think the enhanced throughput of DDR is where you gain your performance, not bus speed. I mean, they're related, but overall, you want the RAM to be able to push more data through in a clock cycle AFAIK. We'll see, because I just ordered a 900 Duron and 512 of DDR to replace my 800 Duron and 512 of SD (got a new mobo too, don't worry ). I'll unlock the Duron of course and run it at 7.5x133, but I'm guessing even at stock speed I'd see a performance boost from the 800 running at 7x133 with the SD-RAM.

Bandwidth bandwidth bandwidth!

-Whir (I think)

Edit: Won day I'll lurn to speel and tipe

[ND]

How do I understand it :
FSB Bandwidth :
AGTL+ (P3) @133MHz : 1.1GB/s
QP (P4) @100MHz QDR : 3.2GB/s
EV6 (Athlon) @100MHz DDR : 2.1GB/s

RAM Bandwidth :
PC133 : 1.1GB/s
PC2100 (PC266) : 2.1GB/s
PC3200 (PC333) : 3.2GB/s
PC800 RDRAM : 3.2GB/s
PC1066 RDRAM : 4.2GB/s

Putting faster RAM on bus which can't take full potential of it is a waste.
For this reason PC600 RDRAM wasn't good for i820 P3 mobos, and todays DDR SDRAM does almost nothing to Tualatin.
And for same exact reason Athlon ruleZ with DDR as well as P4 with RDRAM.

[OuTpaTienT]

Originally posted by ND
EV6 (Athlon) @100MHz DDR : 2.1GB/s

Um, aren't all Athlons now (since XP) 266MHz bus (133MHz DDR)?

[ND]

True, my bad
Typo : should be EV6 (Athlon) @133MHz DDR : 2.1GB/s
100MHz DDR FSB is 1.6GB/s

[squeech]

I agree with ND. Your numbers support what I was trying to say in simpler terms (I'm not sure if it made sense in all those words).

I don't know if I would call it a "waste" of bandwidth, but you do create a bottleneck. I did not mean to say that your system loses performance, because a boost is visible. But rather your RAM runs into a wall and its full potential cannot be used (I hope that makes sense, I can't even understand me tonight!)

The FSB is more integrated with the memory controller than one might think. This of course does vary a little with different motherboards.

[Richard Cranium]

hmmm->>

when the memory clock runs faster than the frontside bus performance can lag