PC 1066 RDRAM or DDR SDRAM at 266 MHZ

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@obrien040362 wrote:

Recently I configured an 8250 system and 4550 system with everything the same except the type of ram of course.  The  8250 PC1066 RDRAM system was $10 cheaper (it had a better rebate).

My question is with every the same (processor, front side bus, price, hard drive size, etc) would you choose a system with PC1066 RDRAM or DDR SDRAM at 266 MHZ ?

Everyone so far I have talked to says the DDR is better.

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Hi,

Add me to the list.
A would choose the 4550 also.

Mis Dos Centavos,
Darrell
Helping Dell talkers here since 1997
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For what it's worth, I agree with Mitch

Dimension 4400
Windows XP Home Edition, SP1
1600 megahertz Intel Pentium 4
D845PT AAA67834-304 Mother Board
512 Megabytes PC2100 DDR RAM
BIOS: Intel Corp. A04 02/12/2002
40 Gigabyte WDC Hard Drive
16MB ATI Rage 128 Ultra
SoundMAX Integrated Digital Audio
16X CD-RW Drive
Realtek RTL8139 PCI Fast Ethernet
Lexmark X83, Multipurpose
Norton Anti-Virus 2002
External 100MB Iomega Zip Drive
Dell 206, 120V Speakers
Phillips 17" Monitor
Motarola SB4100 Cable Modem

The benchmark test i have seen show pc1066 faster but not twice as fast as  ddr  ?  I  think some of the comments against RDRAM were heat issues.  Also I have seen comments on weather it has the ECC feature.  Does all PC1066 have ECC feature.

from http://www.acme.com/build_a_pc/memory.html

• PC2100 (DDR266), 133MHz DDR, 2.1 GB/s
• PC1066, 533MHz DDR, 2.1 GB/s

obrien,

According to the Acme website, it is showing that RDRAM PC1066 is only 2.1gb/s this info is for single channel the Dell Dimension 8250 RDRAM is Dual-Channel memory so you have to double the numbers, RDRAM PC1066 is 4.2gb/s not 2.1 like the DDR. Now as for Real life performance, SiSoftware Sandra Benchmarks show PC2100 (DDR266) as being anywhere from 1600-2070mb/s Range on Intels i845 series chipsets and PC1066 RDRAM as 3340mb/s on Intels i850 series chipsets, so the PC1066 is still between 1.5 - 2 times faster than PC2100 DDR. 

http://www.deviantpc.com/articles/systembus/p4.shtml

Message Edited by MViani on 12-22-2002 02:16 PM

"Not sure, but I have been told that the PC1066 produces a LOT of heat ...."

I'm not sure either, but I think what it is about RDRAM isn't that the whole stick produces a lot of heat compared to similar speed SDRAM, it's that certain chips in the package get a lot hotter than the other ones.  I think this is due to the serial nature of the memory and that the different chips cycle from being on and off and in between.  This is why you see almost all RDRAM come with the little metal heat spreaders on them, not to cool the whole stick down per se but to spread the heat out among the hotter and cooler chips in the package, whereas only the higher end SDRAM comes with heat spreaders from the factory, and in this case the purpose is not so much to even out the heat but to help with heat dissipation on the whole stick.

"Everyone so far I have talked to says the DDR is better."

You cannot deny that PC1066 RDRAM is faster.  It simply is.  Look up any hardware site and look at their benchmarks.  The RDRAM wins nearly every single time, even edging out the Granite Bay/dual channel DDR combo which has the same theoretical max. bandwidth.  Now, DDR IS cheaper, and probably has a longer future ahead of it that Rambus, but it is NOT faster at stock speeds.  Now as to whether it is "better" that is up to you. 

DDR is cheaper.  It will cost less to add more RAM with DDR.  But it will probably cost you the SAME to add more AND replace your motherboard so that it runs at a similar speed to Rambus.

DDR can probably be used in your future motherboards.  But that does not help you right now, as you do not have a future motherboard, and a future motherboard will cost you $$$.

DDR is, right now slower. 

What I would do if I could, and I couldn't live with the idea of buying a slightly slower system, is wait until the new motherboards are out and then buy a DDR based solution.  Or if you really must have the fastest now, I would get RDRAM and then take it up the behind when I add more RAM.

Non ECC is generally cheaper, and most people who are not using their computers as servers nor to process data that is critical to their businesses do not need the capabilities of ECC.  I have also heard ECC is also slightly slower.  Being a cheapskate myself I would go for non ECC for home use.