Any real difference between PC800-45 and PC800-40 RDRAM?

RanDum72

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Feb 11, 2001
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Intel specified that you can use PC800-40 with P4 processors running at 533mhz FSB (memory still at PC800 speeds of course) but PC800-45 is only for 400mhz FSB CPU's. Why is that? If the memory bus is still running at PC800 speeds, is there a difference between 45 and 40ns speed memory?
 

sean2002

Golden Member
Apr 9, 2001
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Originally posted by: unsped
5ns

Well if you want to say that then lets dig a little further, ok, RAMBUS chips are at 40NS, SDRAM is at 5NS, then why isn't SDRAM 8X faster than RAMBUS





sorry had to do it



Dual channel PC-1066+ 4.26GB of bandwith................. that can be utilized by the P4




 

ElFenix

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Mar 20, 2000
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i dunno but i know that 45ns stuff doesn't work with 133mhz fsb systems. sounds like intel got something wrong in their memory controller.
 

dexvx

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Feb 2, 2000
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Originally posted by: ElFenix
i dunno but i know that 45ns stuff doesn't work with 133mhz fsb systems. sounds like intel got something wrong in their memory controller.

Nope, you're wrong. 45ns RDRam newer revisions (key word is newer) actually clock to higher speeds than their 40ns RDRam counterparts. Go look at some extreme RDRam overclockers' webpages. I have no explanation as to why, but it just is.
 

GrumpyMan

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May 14, 2001
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Originally posted by: dexvx
Originally posted by: ElFenix
i dunno but i know that 45ns stuff doesn't work with 133mhz fsb systems. sounds like intel got something wrong in their memory controller.

Nope, you're wrong. 45ns RDRam newer revisions (key word is newer) actually clock to higher speeds than their 40ns RDRam counterparts. Go look at some extreme RDRam overclockers' webpages. I have no explanation as to why, but it just is.

Yep, read that in many forums. 45ns clocks higher for some reason, don't bother getting 40ns.
 

RanDum72

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Feb 11, 2001
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So I actually have a better chance of hitting PC1066 speeds with 45ns PC800 than 40ns PC800? What are some good RDRAM? Samsung? Is Elpida a good brand?