Epox 8RDA+ RAM incompatibility

[time]

This is a caution mainly for Australian readers, although the product concerned is exported to a number of countries.

Legend PC2700 DDR-SDRAM modules are currently incompatible with Epox 8RDA+ (nForce 2) motherboards when run at their rated speed of 166MHz. Legend is working on the problem.

The modules may be okay at 133MHz - the board booted for me at 150MHz, but I didn't try any extensive stability testing. At 166MHz it won't even POST, regardless of timings.

Presumably the problem does not affect all nForce 2 boards, because Legend also distributes MSI. FWIW, Legend usually uses Hynix chips in their DRAM modules.

In contrast, I found off-the-shelf Transcend DDR333 ran successfully at 190MHz (CAS 2.5). It was retail packaging, but supposedly there is no difference between this and OEM (or so I've been told :-? ).

What I found particularly impressive was achieving stable operation with CAS 2 at 178MHz (5-2-2-2). My experiences with Transcend products (including flash memory) over the last six months have been great.

 

[Tea]

We uzed some Transcend motherboards for a while, oh, maybe a couple of years ago. They worked just fine. Legend RAM, IMO, is always wonderful or horrible, depending on if it likes the board or not. Usually it's fine. But we have had instances before where it was incompatible. If you call them, they go out of their way to help. (As you know.)

 

[LiamC]

I have been struggling with the 8RDA+ as well. Crucial PC2700 is also incompatible - yet works fine with their PC2100 or PC3200. Go figure.

 

[blakerwry]

what chips are on that PC2700?
Is this a widespread issue or just something yuo've noticed with your equipment?

I've noticed that Crucial seems to have a few brands of PCB's and chips on their RAM...

Is it possible that a stick with Samsung modules and Samsung PCB could have been modified so that it somehow is not compatible(while a non-crucial samsung/samsung combo would be)?


just wondering...

 

[LiamC]

Blakerwry, I only have PC2100, but in searching for answers to my troubles I came across this -

http://www.nforcershq.com/forum/viewtopic.php?t=9486

 

[blakerwry]

They seem to have put it back on the 8rda+'s compatibility list...

 

[GMac]

Hmm - Crucial listed their PC2700 as being compatible when I bought the 2 sticks of 512MB for my 8RDA+, and they're running happily (albeit at 133), so this is a bit mystifying......

GM

 

[LiamC]

The answer is probably not black-and-white.

The "incompatibility" could be as simple as a wrongly programmed SPD. Anyone who sets their RAM timings manually would find a setting that works and so not suffer the incompatibility.

Also, Crucial use memory chips from manufacturers other than Micron - Crucial <> Micron - and it could be restricted to PC2700 modules using a certain type of chip.

It could also be restricted to a certain 8RDA+ BIOS.

It could be a figment of the imagination, though I did read somewhere that Crucial were exchanging modules so they must know something.

I sure more learned people in the biz could come up with other reasons as well. My post was more a "heads up" than definitive.

 

[time]

I have two of the Legend PC2700 sticks (256MB each). A customer decided he wanted 512MB instead of 256MB, so I decided to use them in a Gigabyte 7VAX (KT400) instead.

Guess what? In this board, they won't work even at 133MHz! :boom:

The PC posts alright, but any attempt to run (or install) Win2k throws up an error. Because I'd changed a couple of other things as well, I had already hosed off C drive before I cottoned on to what was happening.

Again, Transcend DDR333 worked without a hitch.

The Legend PC2700 appear to use the same series of chip as the PC2100, so I have no idea why they behave so differently. Here are the product numbers, for anyone who's interested:

Legend L3264D35 - 643HDC5A (256MB PC2100)
Hynix 234A
HY5DU56822AT-H

Legend L3264D36 - 643HDC5A (256MB PC2700)
Hynix 304A
HY5DU56822AT-J