Help with 3 DIMMS of RAM on the motherboard

Previously Melissa.Shanhun RemoveThis @gmail.com wrote:
> I've currently got 3 DIMMS of DDR2 Ram installed on my ASUS
> motherboard 2x512Mb in A slots 1 &2 which have worked fine for 3-4
> years and 1x2Gb in B slot 1. Now Windows sees 2Gb of RAM and if I swap
> them over (1x2Gb in A slot 1 and 2x512Mb in B slots 1 &2) the PC just
> doesn't run properly. Any suggestions of how to get that extra gig of
> RAM working?

> thanks so much!!

What board? If it is an AMD Athlon 64, then you are
out of luck, since you need the same modules in all
banks. Same size is not enough, AFAIK.

Arno
 >> Stay informed about: Help with 3 DIMMS of RAM on the motherboard 

> What board? If it is an AMD Athlon 64, then you are
> out of luck, since you need the same modules in all
> banks. Same size is not enough, AFAIK.
>
> Arno

I encountered similar difficulties when I added 2GB to an M2A-VM HDMI
board.
Asus tech support echoed your sentiments yet a BIOS upgrade solved the
problem and now my O/S and BIOS see all 4GB of DDR2 RAM.
IOW, you don't need the identical modules from the same manufacturer
in order
to make things work. Just wanted to clear the air on this issue.
 >> Stay informed about: Help with 3 DIMMS of RAM on the motherboard 

Previously Sudsy <sudsy2222.RemoveThis@yahoo.com> wrote:
>> What board? If it is an AMD Athlon 64, then you are
>> out of luck, since you need the same modules in all
>> banks. Same size is not enough, AFAIK.
>>
>> Arno

> I encountered similar difficulties when I added 2GB to an M2A-VM HDMI
> board.
> Asus tech support echoed your sentiments yet a BIOS upgrade solved the
> problem and now my O/S and BIOS see all 4GB of DDR2 RAM.
> IOW, you don't need the identical modules from the same manufacturer
> in order
> to make things work. Just wanted to clear the air on this issue.

Well, it is sometimes possible to find a superset of RAM parameters
that all modules work with. The historical issue that RAMs could have
different internal organization is gone, AFAIK, so it is all timing.
Typically RAM still works when using a slower timing. It depends
a bit on luck. But you are correct that in some cases (no
idea whether majority or minority) it can be made to work.

However 3 DIMMs are different. This means an entirely different
configuration in both banks. I am not even sure the Athlon 64
CPU itself (or rather its memory controller) can support that.
I have not seen it or anything similar advertized as possible
in several Athlon 64 mainboard manuals.

Arno
 >> Stay informed about: Help with 3 DIMMS of RAM on the motherboard 

<snip>
> However 3 DIMMs are different. This means an entirely different
> configuration in both banks. I am not even sure the Athlon 64
> CPU itself (or rather its memory controller) can support that.
> I have not seen it or anything similar advertized as possible
> in several Athlon 64 mainboard manuals.
>
> Arno

I beg your parsnips. Three sticks is certainly a different problem
since you're
going to end up mixing dual channel and single channel. I wouldn't
image
that you'd get very good performance out of such a configuration.
Apologies
for speaking out of turn.
 >> Stay informed about: Help with 3 DIMMS of RAM on the motherboard 

"Sudsy" <sudsy2222.RemoveThis@yahoo.com> wrote in message
news:bb7106d5-0609-4f39-a161-d0f54fe3e0ea@e4g2000hsg.googlegroups.com...
> <snip>
>> However 3 DIMMs are different. This means an entirely different
>> configuration in both banks. I am not even sure the Athlon 64
>> CPU itself (or rather its memory controller) can support that.
>> I have not seen it or anything similar advertized as possible
>> in several Athlon 64 mainboard manuals.
>>
>> Arno
>
> I beg your parsnips. Three sticks is certainly a different problem
> since you're
> going to end up mixing dual channel and single channel. I wouldn't
> image
> that you'd get very good performance out of such a configuration.
> Apologies
> for speaking out of turn.

Most likely the machine can run 3 dimm banks as single channel, but the
machine will take a 3% - 5% performance hit.
 >> Stay informed about: Help with 3 DIMMS of RAM on the motherboard