SC Tom wrote:
Years and years ago, there used to be these adapters that you could plug
2 sticks of RAM in to increase the amount memory in each slot (had some
on an old 386 or 486 PC).
Are they still being made that would work on DDR3 RAM, or are the newer
memory speeds making that unstable? I have a number of 8GB sticks around
and would love to bump my desktop from 16GB to 32GB, just for grins 'n
giggles (and without spending big bucks on 2 16GB sticks).

Thanks!

I haven't seen anything like that.

Intel doesn't generally rate their desktop stuff for four ranks
(four rank DIMMs on servers, hide behind buffers on control/address).
So the address loading is too much.

It's true though, that on an microATX where they only put
two DIMMs, there might be sufficient drive for four DIMMs.
Only a few of the signals (perhaps CS chip select) might be
overloaded. And you also need a solution for clock signals.

Conceptually, you have offerings like this.

UDIMM no buffers (your 8GB stick)
RDIMM buffers on control/address, 32 or 36 chips, four ranks
FBDIMM buffers on control/address/data, with design differences
with respect to the RDIMM (continuity requirement?)

Another small issue, is the mechanical spacing. A two-DIMM board
could use a "left" and a "right" dual module, and not bang
together. A four-DIMM board, you might be able to go from
four DIMMs to six DIMMs, but maybe a config to make eight
work would be too hard.

As a general trend, you might notice that companies no
longer "invest" in stupid stuff. I see fewer of the
exotic offerings, and I expect this is because the
companies that do those, take a "bath" on the NRE.
If it was just a PCB and a few piece parts, I could
see someone taking a chance. If it was custom silicon,
definitely not. You might need some tricky pad driver
work, and from what I've seen of the skill set of
pad driver designers, there aren't enough of the right
people to do stuff like that.

And then there's the issue of patents. You would be
surprised what items "don't exist" because of patents.
Sucks, when no one can serve a potential market
because of them. If you made custom silicon to make
something like that work, then a patent vulture
would eat your lunch.

Paul