KT266A vs DDR400 - RAM not recognised.

[AD.]

Hi all,

I'm trying to upgrade the RAM on a GigaByte GA-7VTXE (VIA KT266A chipset),
from 512MB of DDR266 to 1GB.

Now there wasn't any DDR266 available, so I'd thought I'd get a 512MB
stick of DDR400. I know the KT266A doesn't support DDR333 or DDR400, but I
assumed it would just run fine at DDR266 speeds, and that it could go into
a faster mobo later if it ever wanted to run at full speed.

Is there any thing fundamentally wrong with that assumption?

The mobo doesn't recognise the new DDR400 stick. It either just sits
there and beeps when it's the only stick installed, or with both old and
new installed the machine works fine but only recognises the old stick.

Cheers
Anton

 

[Nate Edel]

Now there wasn't any DDR266 available, so I'd thought I'd get a 512MB
stick of DDR400. I know the KT266A doesn't support DDR333 or DDR400, but I
assumed it would just run fine at DDR266 speeds, and that it could go into
a faster mobo later if it ever wanted to run at full speed.

Is there any thing fundamentally wrong with that assumption?

It should work, in terms of the speed, but:
A) Does your motherboard support 512mb sticks at any speed?
B) Did you get registered memory instead of unbuffered?
C) Did you get ECC memory instead of non-ECC?

Lastly, have you tried the DDR400 stick in another system that's known to
take DDR400 OK?

 

[AD.]

It should work, in terms of the speed, but:
A) Does your motherboard support 512mb sticks at any speed?
Yup.

B) Did you get registered memory instead of unbuffered?
Nope.

C) Did you get ECC memory instead of non-ECC?
Nope.


Lastly, have you tried the DDR400 stick in another system that's known to
take DDR400 OK?

Yeah, that's the thing. We don't have any of those lying around, it was our
flashest machine

Thanks Nate. I think I'll have to RMA it for a different brand, maybe even
for a DDR333 stick.

Cheers
Anton

 

[Tony Hill]

Yeah, that's the thing. We don't have any of those lying around, it was our
flashest machine

Thanks Nate. I think I'll have to RMA it for a different brand, maybe even
for a DDR333 stick.

There's a good probability that it's a memory density issue. New
memory is made with higher density chips (more bits on a single chip)
that older motherboards often don't support. Chances are that you're
new DDR400 memory is made with 512Mbit or even 1Gbit memory chips,
while the old KT266A chipset might only support up to 256Mbit chips.

It's pretty easy to figure out the density of the memory chips, just
divide the total chip size (512MB) by the number of chips on the
module. Eg, if there are 16 chips on the module (probably 8 per
side), then you've got 32MB (256Mbit) per chip. If the module has
only 8 chips on it, then they are 64MB (512Mbit) chips. 4 chips means
they're 1Gbit a piece.

Also, before giving up hope entirely, you might want to try flashing
the motherboard to the latest revision of the BIOS if you haven't done
so already. This can often make a big difference when it comes to
supporting newer memory.

In any case, the speed is not an issue, DDR memory is fully backwards
compatible in terms of speed. However there are a lot of other
potential compatibility problems that are totally unrelated to speed.

 

[Nate Edel]

Nope.

Well, those were the three really obvious ones.

Yeah, that's the thing. We don't have any of those lying around, it was our
flashest machine

Ah well. If you have another PC2100/2700 machine around you could try it in
there.

Thanks Nate. I think I'll have to RMA it for a different brand, maybe even
for a DDR333 stick.

May be safer to go with DDR333, but as far as I know, DDR400 should work in
the older machines if everything else is a match.

 

[George Macdonald]

Hi all,

I'm trying to upgrade the RAM on a GigaByte GA-7VTXE (VIA KT266A chipset),
from 512MB of DDR266 to 1GB.

Now there wasn't any DDR266 available, so I'd thought I'd get a 512MB
stick of DDR400. I know the KT266A doesn't support DDR333 or DDR400, but I
assumed it would just run fine at DDR266 speeds, and that it could go into
a faster mobo later if it ever wanted to run at full speed.

Is there any thing fundamentally wrong with that assumption?

The mobo doesn't recognise the new DDR400 stick. It either just sits
there and beeps when it's the only stick installed, or with both old and
new installed the machine works fine but only recognises the old stick.

I wonder if it might be an SPD issue - IOW the SPD of the new DDR400
contains values which are outside the range that the BIOS knows about. If
you haven't tried a BIOS update that'd be first. Second thing would be to
go into BIOS Setup with only the old DIMM in, turn off SPD and set
conservative timing values manually, then try with the new DIMM.

The other thing is which slots are you putting the new DIMM in? If it's a
slot which has never had anything in it before, the contacts could be
grunged up a bit.

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??

 

[AD.]

I wonder if it might be an SPD issue - IOW the SPD of the new DDR400
contains values which are outside the range that the BIOS knows about. If
you haven't tried a BIOS update that'd be first. Second thing would be to
go into BIOS Setup with only the old DIMM in, turn off SPD and set
conservative timing values manually, then try with the new DIMM.

Thanks everyone, got the DIMM working in another machine that I thought
had the same mobo but it turns out it was a slightly different one: a
GA-7VTXE+ as opposed to the nearly identical GA-7VTXE.

Thanks again

Cheers
Anton

 

[Zoo Loo]

There's a good probability that it's a memory density issue.

Interesting.