RDRAM PC1066

[rpdc]

I have a Gigabyte mobo (GA-8IHXP) with 128MB PC1066. I want to add 512MB. I have found 256MB PC1066 for $126.36 at 2 buystore.com. The brand is Memorex. Has anyone had experience with Memorex RDRAM or this site?

 

[jammydodger]

It might be cheaper for you to Get and new motherboard that supports DDR RAM, in dual channel this will be faster than RDRAM.
If you have a P4b (133Mhz bus) then you could get an Abit IS7 and 2x256MB PC3200 DDR. If you have a P4A then stick with RD RAM or get a new CPU.

<font color=blue>P4c 2.6@3.25
512Mb PC4000
2x120Gb 7200.7 in RAID0
Waterchill KT12-L30
Abit AI7
Radeon 9800Pro
</font color=blue>

 

[Crashman]

He'd have 768MB of RAM for around $250. He'd pay more to get a cheap board and cheap PC3200, and his system would be SLOWER! That's because PC1066 dual channel is faster than PC2100 dual channel when used with 533 bus P4's. Unless you're willing to suggest he also buys a new CPU. You see, PC2100 speed dual-channel is synchronous for 533 bus CPU's, as is PC1066 dual-channel.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

 

[jammydodger]

Isnt PC1066 still 16bit? So has to be used in matching pairs? Or were the PC1066 modules 32bit?

<font color=blue>P4c 2.6@3.25
512Mb PC4000
2x120Gb 7200.7 in RAID0
Waterchill KT12-L30
Abit AI7
Radeon 9800Pro
</font color=blue>

 

[Crashman]

PC1066 is DDR1066 RDRAM (as opposed to DDR266 SDRAM). It operated at an actual frequency of 533MHz, and was 16-bit. So a pair is 32-bit. But its base clock is 4x as high as PC2100.

So DDR SDRAM has 4x as wide a pathway, but RDRAM is clocked 4x as high. PC1066 became RIMM4200 when put on a 32-bit module, where 4200 stood for the bandwidth of 4200MB/s. That's 2x PC2100, but you can do Dual Channel with PC2100 as well.

What all that means is that PC1066 gets you 4.2GB/s (in dual channel mode like the i850 provides), and PC2100 Dual Channel gets you 4.2GB/s. So with a 533 bus P4, which also has 4.2GB/s bandwidth, it's a wash.

But for some reason PC1066 turned out to be slightly better performing than PC2100 dual channel. And running your RAM at faster than PC2100 speed in dual channel doesn't make sense with the 533 bus P4, it gains you nothing. Still, if he HAD to change platforms I'd tell him to get PC3200, so he could use it with a future processor upgrade.

At any rate, he'd save SOME money going with more PC1066, over replacing the board and RAM. And for some odd reason, given equal bandwidth, RDRAM on the i850 beats DDR on the 865. The main reasons RDRAM was dropped is that 1.) it wasn't fast enough to keep up with PC3200 (dual channel) on the 800 bus P4, 2.) Public resentment over forced RDRAM 3.) Expense.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

 

[jammydodger]

Well if he did get 2x256 PC1066 RDRAM then he would have to dicard his 256meg because RDRAM has to use matched pairs right?
I dont know about in america but over in the UK 2x512 PC1066 RDRAM will prob cost you more than 2x512 PC3200 DDR (thats if you can still get hold of the RDRAM). It just seems a waste to spend a lot of money on an obsolete memory type when he could spend a little more and get a new board aswell. Then later he could get an 800Mhz FSB chip.

<font color=blue>P4c 2.6@3.25
512Mb PC4000
2x120Gb 7200.7 in RAID0
Waterchill KT12-L30
Abit AI7
Radeon 9800Pro
</font color=blue>

 

[Crashman]

He'd be able to use both pairs, it's not a problem.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

 

[juin]

You know that I875 with DDR 400 was less that 7% faster that I850E with Pc1066.

RDRAM is much faster at equal rate.So unless he move to faster FSB top notch PC3200 there wont be any gain.

i need to change useur name.