goldstein@delni.enet.dec.com (Fred R. Goldstein) (12/14/89)
I have a J. Random Clone, genus 286, store-brand species, that uses
a Suntac Baby-286 motherboard. This is a fairly common cloneboard
(very recent vintage) that implements LIM4.0 EMS on the motherboard,
with a DIP switch that makes all memory above 640k either EMS or
expanded. It's switchable 12/6 MHz and works quite nicely. BUT
According to its manual (and this is all the store knows), there are
a half-dozen ways to populate it with memory. Mine came with 1M,
and that's done using 8 44256 chips and a couple of parody :-) chips.
More than half of the memory area is vacant. If you're to populate
the board with 2M or 4M, though, you use 411000 chips, NOT 44256s.
(I may have the numbers wrong, but my 1M config uses 4x256k chips
and the 2M/4M configs use 1x1M chips, which are a bit more common.)
I'm not real happy that upgrading means I have to swap out all the
existing memory. Does anyone know if that board has any undocumented
options for adding memory beyond 1M without displacing the 44256s?
Thanks,
fred
--------
No snappy signature. Someday I'll figure out how this user agent
implements .sig files. cs4g6ag@maccs.dcss.mcmaster.ca (Stephen M. Dunn) (12/17/89)
In article <6870@shlump.nac.dec.com> goldstein@delni.enet.dec.com (Fred R. Goldstein) writes:
$I have a J. Random Clone, genus 286, store-brand species, that uses
$a Suntac Baby-286 motherboard. This is a fairly common cloneboard
[...]
$a half-dozen ways to populate it with memory. Mine came with 1M,
$and that's done using 8 44256 chips and a couple of parody :-) chips.
$More than half of the memory area is vacant. If you're to populate
$the board with 2M or 4M, though, you use 411000 chips, NOT 44256s.
$I'm not real happy that upgrading means I have to swap out all the
$existing memory. Does anyone know if that board has any undocumented
$options for adding memory beyond 1M without displacing the 44256s?
Hmm ... either you have a more recent version of the Suntac motherboard
than I do, or the use of 44256s is an undocumented option in the revision of
the motherboard manual that I got (not that it's much of a manual anyway ...
the english is awful and it looks like it was produced in about 15 minutes).
The options for my board are:
512K 18 x 41256
640K 18 x 41256 + 18 x 4164
1M 36 x 41256
2M 18 x 511000
4M 36 x 511000
So when I upgraded from 640K to 1M, I had to swallow those 4164s (not
that they're worth much anyway) ... what I'm not looking forward to is
the 36 41256s I'll have to swallow if I upgrade beyond 1M before buying
a new machine.
--
Stephen M. Dunn cs4g6ag@maccs.dcss.mcmaster.ca
<std_disclaimer.h> = "\nI'm only an undergraduate!!!\n";
****************************************************************************
If it's true that love is only a game//Well, then I can play pretendakcs.amparsonjr@vpnet.UUCP (Anthony M. Parson, Jr.) (01/03/90)
The last two messages are really the first two that showed concern over eventual upgrading, and the waste of the original RAM. I'm contemplating getting a 386 mboard, which (most of them) can have 1 or 2 meg with 256K chips, or 4 or 8 meg with 1 mbit chips. If you want to upgrade to the max from the included 1st meg of RAM, you'll end up losing $100 or so. Moral, buy 4 ms at the beginning. You won't have to wste any when adding.
emmo@moncam.co.uk (Dave Emmerson) (01/11/90)
In article <25a1083b:3560.2comp.sys.ibm.pc;1@vpnet.UUCP>, akcs.amparsonjr@vpnet.UUCP (Anthony M. Parson, Jr.) writes: > The last two messages are really the first two that showed concern over > eventual upgrading, and the waste of the original RAM. I'm contemplating > getting a 386 mboard, which (most of them) can have 1 or 2 meg with 256K > chips, or 4 or 8 meg with 1 mbit chips. If you want to upgrade to the > max from the included 1st meg of RAM, you'll end up losing $100 or so. > Moral, buy 4 ms at the beginning. You won't have to wste any > when adding. Good for you! Before you buy though, check that the specs of your DRAMS match the expectations of the upgrade board, there's more to it than just the capacity of the device: access time, page/nibble mode, and package (pinout style) are also important. Some motherboards expect your DRAMS to be on SIMMs or SIPs, though these usually state '256K x 8' (or 256K x 9) as opposed to '8 x 256K'. What about the waste of the rest of the old motherboard though? aren't you throwing away $100 or more there? Who me? A wet blanket? Nah, must've been that bed-bath.... Dave E.
akcs.amparsonjr@vpnet.UUCP (Anthony M. Parson, Jr.) (01/13/90)
Since I posted the original msg, I have taken delivery of an AMI board, with 4 meg of 80 ns RAM, and 64K cache. 256K of ROM includes diags,setup. RE: waste of the original motherboard that is being replaced, you are right. However, I'm building a new machine and decided to keep the turbo XT as a working spare (I have enough parts here to do this). By keeping open space on the XT's AboveBoard 286 expanded memory card, if I upgrade the XT to an 80286, I'll still have a spot for the AboveBoard 286 and the XT mother board ram. Used XT motherboards are fairly cheap. Yes, a waste, but I'l