On Thu, 02 Mar 2006 12:56:19 +0000, curls
<(E-Mail Removed)> wrote:
>A few months back, I bought a Biostar iDEQ 210v mini PC
>http://www.biostar.com.tw/products/barKM400)ebone/ideq/210v/index.php3
>to replace my old one after the mother board gave up the ghost. I
>bought this particular one as I could use my original CPU, an Athlon
>XP1800. I also bought 512 meg DDR PC3200 memory. Since I had 512 meg
>of PC2700 out of the old computer, I though, "Hmm, what if?" I put it
>in, took it out, shook it all about, but couldn't tell any difference
>in the speed of the computer, and had no errors at all. Both memory
>sticks have been in now for about three months with no seemingly
>adverse effects. So my question is, what *should* I be experiencing by
>installing the slower memory?
Athlon XP1800 uses 133MHz/DDR266 FSB. The optimal memory
bus speed for it is 133MHz/PC2100, with the memory timings
lowered as much as possible. In other words, take a random
PC3200 module rated as 3,4,4,8 timings and run it at PC2100
speed and it'll probably do 2.5,3,3,x or 2,3,3,x or maybe
even 2,2,2,x.
Above I used "X", because on some boards like nForce2, the x
is a faster timing at around 9-11, but on yours (KM400),
keeping it lower like 6 would be better.
HOWEVER, your board has integrated video. IF you are using
the integrated video instead of a separate video card, the
above settings are no longer optimal. You take a slight
performance hit (sometimes trivial) to use the asynchronous
memory bus for CPU performance, but your integrated video
benefits from the higher memory bus speed. So with a 133MHz
FSB CPU, your memory bus would be set to 166MHz, PC2700
speed so long as you use the integrated video.
So your upper target is PC2700 spec'd speed, 166MHz mem bus.
You might as well have two PC2700 modules then, as your
PC3200 module will simply be running at PC2700 speed either
way- with it alone or with both modules installed. "Might
as well" doesn't mean you need to change anything, only that
given the CPU and chipset, the PC3200 is only potential you
aren't able to exploit at the moment... except that as with
the case of the memory downclocked to PC2100 above, PC3200
memory running at PC2700 speed may also allow tigher (lower)
memory timings, though your PC2700 module, if older, may
already be the limit on how fast the timings can be set.
In other words, it's fine as-is, probably not worth trying
to change.