I am trying to upgrade my machine from 1 GB (2x512 sticks) to 3 GB
(3x1024).
The motherboard is a Gigabyte K8NS Pro. Each stick is DDR 1GB,
400MHz, CL3.
So, here's the situation. When I install just a single GB stick and
power up, it boots. I've tried with each stick and it works. However,
when I power down and add a second stick of 1 GB, hhen I power up it
gets stuck on the "DualBIOS" entry screen and it says 2094802
(whatever, 2 GB) Memory Testing: OK. But it just freezes there. When
I try to hit Del to enter setup mode, I get nothing.
Finally, when all three 1GB sticks are in and I power up, it won't
boot, the screen remains black and this beeping sound happens ever 3 or
4 seconds. And, of course, when I put my original RAM back in, it all
works fine.
Is this possibly a voltage problem? It seems strange to me that each
stick works on its own but when used in tandem nothing works. Thanks
for your help.
You have to realize that the Athlon64 processors have some
limits, as to how fast they can drive memory.
Is your board the S754 one ?
On the S754 boards, the AMD processor has two address busses.
One DIMM slot is driven by one address bus. The other two DIMM
slots are driven by the second address bus. If you stuff two
DIMMs into the slots that share address, the BIOS is supposed to
turn the memory clock way down. Placing a DIMM in slot 1
and slot 3 will likely give you one DIMM on each bus, which
puts equal loading on each address bus. (The data bus part is
still shared by the three DIMMs, but driving address is the
hardest thing to do, as the chips on the DIMMs are sitting on
the address bus in parallel. On the old Nforce2 chipset, they
fixed this issue, by having an address bus per DIMM.)
Motherboards are supposed to include the AMD table of
clock rates versus configuration information. In fact, not
all the manufacturers ship that table exactly as AMD states
it - some of them modify the table (make the settings more
aggressive), implying they have done their own testing.
To get you the AMD table, have a look at Table 42 on
page 175 here:
http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/26094.PDF
Now, the next thing to note, is they mention x8 and x16
chips. A 1GB module can be constructed for example, with
(16) 64Mx8 chips. The 16 chips form two ranks of chips
64 bits wide, which is popularly termed "double sided".
Now, have a look here. This company sells modules with
(16) 64Mx8 (expensive) and (16) 128Mx4 (cheap). If I am
to believe that AMD table, you should not be using the
cheap modules. A freezing computer could be a symptom
of the overload caused by a module made with x4 unbuffered
chips. (The 16 chips on the cheap module, actually form
a single rank. Certain of the signals are getting 16 loads,
instead of the 8 they might otherwise get from a rank.)
http://www.portatech.com/catalog/memory.asp?ID=285
To summarize, if you wish to keep decent memory speeds,
you should use 2x1GB, and place them so there is one
DIMM per address bus. I would try the two DIMMs in
slot 1 and slot 3, as I cannot tell by the layout
or by the Gigabyte manual, as to which slot is on
which address bus. I would also try to get some
info on the module, as to its construction. Many of the
"web order only" shops will try to foist the x4 modules
onto people, leaving them with little recourse. I
term such modules, "restocking fee modules", as they
will travel back and forth between customer and
retailer, generating a fat restocking fee each time.
The retailer only has to own one module, which generates
plenty of revenue over the period of a year
I sure hope you have not bought some of those.
This is what a module with proper construction looks like:
http://www.valueram.com/datasheets/KVR400X64C3A_1G.pdf
The rest of the module list is here (assuming I got the
right motherboard model name).
http://www.ec.kingston.com/ecom/con...K8NS+Motherboard&distributor=0&submit1=Search
Paul
