ddr compatibility help

[dani82]

i have no idea on what type of ddr i should buy for an athlon 2200 xp, the manual said the mobo(ecs k7vta3 v8) supports pc2100/pc1600, and not to uses ddr266(pc2100) for stability reasons, but to uses ddr400/ddr333, which is neither pc2100/pc1600

can someone explain this to me?

[Soulhunter]

Only stuff I know...

- SIMM
- SODIMM

- PC66 SDRAM
- PC100 SDRAM
- PC133 SDRAM

- DDR266 PC2100
- DDR333 PC2700
- DDR400 PC3200

- RDRAM PC600
- RDRAM PC800
- RDRAM PC1066

Maybe its a typo in the manual... :confused:


Bye

[vinkes]

Those ecs manuals are pretty vague, but what they mean is this:

if fsb is 133, you can use pc2100/pc2700 ddr memory. not pc1600,pc3200
if fsb is 166, you can use pc2100/pc2700/pc3200 not pc1600
if fsb is 200, you can use pc2700/pc3200 not pc2100 or pc1600

I had a similiar experience with those nice ecs manuals. Anyway, I shouldn't worry about memory, your athlon xp 2200+ has 133(266)mhz fsb, so buy some nice pc2700 memory and everything should be oke.

[Mnl]

I think vinkes is right - exept from the fact that using pc 2100 with fsb set to 166 and using pc 2700 with fsb set to 200 cannot be correct unless you want to run your ram out of spec.

pc 2100 corresponds to a fsb of 133 mhz and pc 2700 corresponds to a fsb of 166. That means that pc 2100 are ment to be used with a maximum fsb of 133 and that pc 2700 with a maximum fsb of 166 mhz.

That said I have from time to time experienced strange problems with ddr ram modules - an example: A friend of mine bought a Asus P4P800 Deluxe MB. To go with it he bought two modules of Kingston HyperX pc 3200 256 mb. This combination ought to work just fine as pc 3200 ram are ment to be used with a 400 mhz fsb. But the system turned out to be totally unstable. When he switched to pc 3200 modules from other brands, the system worked just fine. He even tried two other HyperX pc 3200 modules which he lent at the store, and the system was still unstable. In the end he had to use HyperX pc 3500 to make the system stable. So I guess the morale of the story is that unless the mother board manufactorer guarantees stability for a specific combination of mother board and brand of ram you can't really be sure of anything before you have tested the specific combination.

I don't know about ESS, but I know that some manufactorers lists ram modules which have been tested with their motherboards.

[Solo]

I would rather get some DDR400 as you will be able to run it at DDR266 speeds as well. Plus when you run DDR400 at DDR266 speeds you can usually run it with better memory timings resulting in better performance.

[vinkes]

Originally posted by Mnl
I think vinkes is right - exept from the fact that using pc 2100 with fsb set to 166 and using pc 2700 with fsb set to 200 cannot be correct unless you want to run your ram out of spec.


with most (modern) motherboards fsb and ddr speeds can run async. so you can use lower or higher clocked ddr memory with a given fsb speed. The problem with this is that system performance with go down.

@Solo:
you're absolutely right, expect ecs manuals say you can't ran 400mhz ddr if you have a 266fsb processor installed, which i think is a load of crap ;) .

[JaTeMaTec]

To first answer:

(- DDR400 PC3200)

- RDRAM PC600
- RDRAM PC800
- RDRAM PC1066

The uppermost is the cutting edge at AMD Athlon 32 bit Mobo's and processors today and one must be very carefull when choosing DDR400's (PC3200 = 2x200=400), because the 'cheapest ones' are alike to get you in trouble especially with MoBo's published half year ago and that later...

I would choose Kingston Valueram PC3200 buffered and with parity, that costs a bit more but is worth of it and does have lifetime quarantee!

The last three goes to Intel-section and there the numbers are telling the real FSB from 600 to 1066 mHz. I do not get that one point why AMD is so damn sensitive for 400 mHz FSB and they haven't implemented nothing clever to get over those limits. (In specs of the upcoming 64bit architechture MoBos and new barnd processors there are mentions to get the FSB as up as 600 mHz.)

Ok - i understand this all partly, because of the prices - good AMD 3200+ 512 L2 and 400 FSB both CPU and RAM is very cheap combination to ordinary consumers and beats Intel (with same processing speeds) with price at least 50 to 60 percent in that speed-class and maybe more at near future ...

Here's a link to get some info & specs (AMD Opteron 64 bits etc):
http://www.cpuplanet.com/knowledge/

and at http://www.cpuplanet.com/ you'll find some very new infos of fe. M$ offering Windows XP 64bit as a trial to Opteron owners (DL or CD) etc...

JaTeMaTec

[vinkes]

Originally posted by JaTeMaTec
The last three goes to Intel-section and there the numbers are telling the real FSB from 600 to 1066 mHz. I do not get that one point why AMD is so damn sensitive for 400 mHz FSB and they haven't implemented nothing clever to get over those limits. (In specs of the upcoming 64bit architechture MoBos and new barnd processors there are mentions to get the FSB as up as 600 mHz.)


I've you would read the info of the sites you gave, you wouldn't post the quoted information.

Real fsb from a pentium 4? The real fsb goes from 400mhz to 800mhz. 600 to 1066mhz is the rd-ram memory, which is misleading. Rdram uses datawidth of 16bit, whereas ddr-ram has a width of 64 bits.
which means:
pc1066 rdram = 16bits x 533 x 2 = 2132 mb/s
pc3200 ddrram = 64bits x 200 x 2 = 3200 mb/s

Amd not raising fsb speeds has to do with limitations in architecture and migration to athlon 64.

http://www.pc-care.dk/databus/databus-oversigt.php

[JaTeMaTec]

Originally posted by vinkes
I've you would read the info of the sites you gave, you wouldn't post the quoted information.


OK, i will no more bring out misleaded info gotten from others especially in case of Intel! I was just throwing some (wrong) info, that i got from my 'too wise' friend who calls himseld an Intel-Expert (In RAM cases too). Sorry 'bout that (i will punish him hard :) )

Yep - AMD is cheap, but good and for me the 400 mHz FSB both with RAM and my 3200+ Athlon is OK (that is not it's speed as we all know - it's the 'Average Intel Level' as they proudly say...)

Let's leave this like that for my RAMs - i will be happy with my tot. 1.5GB RAM with 3 buffered ecc-parity Kingstons (PC3200). They costed my totally more than my MoBo+CPU+Cooler :)

Peace!

[vinkes]

Originally posted by JaTeMaTec
OK, i will no more bring out misleaded info gotten from others especially in case of Intel! I was just throwing some (wrong) info, that i got from my 'too wise' friend who calls himseld an Intel-Expert (In RAM cases too). Sorry 'bout that (i will punish him hard :) )

Peace!

You don't have to apologize, hardware can be very confusing ;) .

Peace!