[TriLUG] Memory upgrade problems - brainstorming

[Steve Holton]

Summary of suggestions:

On Tue, Mar 25, 2014 at 12:38 PM, Scott Lambdin <lopaki at gmail.com> wrote:

> these don't match?
>
> DDR3 PC3-10600, DDR3 PC3-12800, DDR3 (non-ECC)
>>
>> I purchased four DDR3 PC3-1600 -- 4Gb modules
>>
>
Help me read this, please.
"DDR3 PC3-10600" is one spec for a module (very similar to the original
ones)
"DDR3 PC3-12800" is the spec for faster but presumably compatible modules.
Dell lists both as compatible with this system.

"DDR3 PC3-1600" is what I *think* I got.

*Does "DDR3 PC3-1600" not match "DDR3 PC3-12800" in a way I don't
understand?*

I was basing my assumption on http://en.wikipedia.org/wiki/DDR3_SDRAM


On Tue, Mar 25, 2014 at 11:40 AM, Bill Farrow <bill at arrowsreach.com> wrote:

> Maybe the BIOS does not recognize the newer memory modules. It reads
> the SPD eeprom from each module to identify what they are, and it may
> be trying to look them up in a hardcoded table.
>

Possible.  This box is from an era before 4Gb modules were readily
available.
I would expect an updated BIOS to fix that, but.....



 On Tue, Mar 25, 2014 at 11:38 AM, Jose Lodeiro <lodeiroja at gmail.com> wrote:

> Steve, I would try to reset CMOS as the final troubleshooting step after
> loading the new modules.
>

That may be a 'pull the battery and let it sit' kind of thing.  The BIOS
has
a 'reset to defaults', but I get the sense the BIOS designers we're too
clever to think there would ever be a need to reset the battery-backed
NVRAM.
and I'm not sure what I'd lose if I did that. Last resort.



On Tue, Mar 25, 2014 at 9:59 PM, Steven Tardy <sjt5atra at gmail.com> wrote:

> crucial.com has a great tool to find ram specs for a given system.
>
> what is the exact part number / specs of this part? could be numerous
> things(voltage/buffered/ecc/chip-size/spd/etc). without comparing the new
> dimm specs to the specs of ram built/certified for that computer it's hard
> to say if it's compatible and why it's not compatible. typically a faster
> frequency dimm will operate fine at a lower frequency.
>
> what bios version does the system have?


 The Crucial site lists both the DDR3 PC3-10600 and the DDR3 PC3-12800 as
recommended/compatible.

8GB Kit (4GBx2)  DDR3 PC3-10600 * CL=9 * Unbuffered * NON-ECC * DDR3-1333 *
1.5V * 512Meg x 64 *   *  Part #:
CT2367677<http://www.crucial.com/store/mpartspecs.aspx?mtbpoid=3F82D56DA5CA7304>

8GB Kit (4GBx2)  DDR3 PC3-12800 * CL=11 * Unbuffered * NON-ECC * DDR3-1600
* 1.5V * 512Meg x 64 *   *  Part #:
CT4003699<http://www.crucial.com/store/mpartspecs.aspx?mtbpoid=12C22A94A5CA7304>

The modules I purchased are not Crucial(R) Brand but instead generic "CEON
DDR3 1600 4GB CL11" modules.

I was *expecting* to get 1.5V, unbuffered, non-ECC, CL11 or better, and to
the best of my knowledge this is what I received.
I was hoping things such as the die mask size, manufacturing techniques,and
silicon dopant chemistry were implementation details which wouldn't affect
compatibility at the module level.

The BIOS was upgraded to current AA15 (released 9/3/2013) recently (as part
of diagnosis) but that did not correct this problem.

I'm thinking the limitation is in the mainboard, rather than the memory
modules, but I fear my recourse against Dell on a 4-year old machine will
be limited.

-- 
Steve Holton
sph0lt0n at gmail.com