Real bus speeds of Via 266 chipset and DDR

Do you have a question? Post it now! No Registration Necessary.  Now with pictures!

I'm posting to get some advice about REAL bus speeds.

I want to know how much my chipset and processor would benefit from
different memory.  The trouble is that I have become confused by
"effective bus speed" and "actual bus speed" and "nominal bus speed"
and so on.

As you may be tired of hearing (!) I am running a Duron Applebred
1800 in a Via 266 mobo made by Syntax with 768 KB of 133 SD-RAM.  The
BIOS is by Phoenix.  The CPU temp under load is ok at 44 degrees C.  

The manual for the mobo is available at
(OR /

My Syntax mobo can run either SD-RAM or DDR.  I am thinking that I
could upgrade the 768MB of 133 SD-RAM to DDR in order to get an
increase in performnce.  

Then later on this year, I can build a faster PC using all new parts
except for the DDR which I could take from the existing Snytax mobo.  
(I would put the slower SD-RAM back into the Syntax mobo to create a
basic PC.)  I do not want to spend more money than I have to as I am
on a budget.

QUESTION ONE.  What speed DIMM memory would work well with my
Via266/Duron1800 and yet still be good to use with a faster processor  
later this year which will probably be a mid-power socket 939 (and
some mobo chipset which I haven't decided on yet)?  Is PC2700 too

QUESTION TWO.  How fast does the bus on my mobo/cpu actually run
these devices at:

(a)  the "133/266 MHz FSB" on the cpu
(b)  the bus on 133 MHz SD-RAM
(c)  suitable DDR in Q.1 (PC2700 ??)
(d)  the PCI bus.

Thank you guys.

Site Timeline