At 10:47 AM 5/4/00 -0400, Mitch Vincent wrote:
>Hmm, I guess they're trying to be misleading when they say "Up to 4GB of
>memory (PC100 ----> SDRAM <-----)"?
>
>Hmm, there isn't any mention of the nead for RDRAM... Shame on these
>companies for trying to screw people.
No, they're not being misleading...most of the boards either come
without the memory hub, in which case you need RDRAM, or with the
memory hub (which is a separate chip that translates wide SDRAM
data into narrow, serialized RDRAM data, which is why it's slower).
The latter boards only take SDRAM.
Some folks offer hybrid solutions. ASUS has one involving a board
you plug into an RDRAM socket. The board has the memory hub chip
on it, and you plug your SDRAM into that. Some offer i820 boards with
two RDRAM and two SDRAM slots, and you choose which you want to use.
That kind of thing.
As far as 4GB SDRAM, the i840 offers two memory channels and two
memory hubs, which means in principle twice as much SDRAM as with
a traditional BX or i820 board, i.e. 4GB - if they provide enough
slots.
So it sounds like you're looking at a board with the i840 chipset,
memory hub, and SDRAM DIMM slots.
The memory hub wasn't part of Intel's original plan, it was added
last year before rollout because RDRAM availability and price sucks.
Mobo makers have jumped on the memory hub solution because they know
buyers don't want to pay $800 for a 128MB RDRAM DIMM. Current RDRAM
offers no real advantage to PC100/BX for most applications, but it has
lots of upside potential.
But RDRAM on an i840 board DOES offer an advantage because of the
10%-ish penalty associated with the memory hub/SDRAM solution.
Ugh.
- Don Baccus, Portland OR <dhogaza@pacifier.com> Nature photos, on-line guides, Pacific Northwest Rare Bird Alert
Serviceand other goodies at http://donb.photo.net.
