Archived from groups: alt.comp.periphs.mainboard.asus (
More info?)
In article <c833e679.0407130037.1757057d@posting.google.com>,
paul_baker@go.com (Paul Baker) wrote:
> Snip
> >
> > There is mention here, of the fifth multiplier bit. It controls
> > whether the other four multiplier bits give 5.5-12.5 or 13 and above.
> > I suspect that is why your multiplier setting isn't really 16.5, but
> > is from the lower range instead. See "Reader Tips" by user "Omonk"...
> >
> >
http://www.viperlair.com/articles/howto/cpu/unlock/p4.shtml
> >
> > 133 is the CPU clock in MHz. 33 is the PCI bus clock in MHz.
> > Both the processor FSB and the memory operate DDR, transferring
> > two chunks of data per clock cycle. So, FSB266 and DDR266 are
> > perfectly matched for each other, and the numbers are based on
> > 2xclock_rate.
> >
> > HTH,
> > Paul
>
> Thanks for the link, having read it, how do I "cut the L3 bridge"?
In terms of multipliers, some motherboards don't support the
fifth multiplier bit properly. Multipliers have a low range
and a high range, and the fifth bit has something to do with
which range is available. (I'm not an Athlon guy, so I don't
have a complete table of bridge mod versus processor type
stored in my head.)
Multipliers have been "superlocked" on AthlonXP processors since
earlier this year. Attempts to change the multiplier, even if
the BIOS is showing a certain number, are not really working.
If you bought a processor last year, those processors would
likely be unlocked. Your multiplier is locked at 166*11=1833
What I neglected to pick up on, is you have a 166MHz clock processor
running at 133MHz. That is why your current 1466 is not the 1833
it is supposed to be. 1466*(166/133)=1833
1833 (2500+) OPGA 166MHz 512KB 1.65 V 85°C 53.7 W
So, the question is, can your motherboard support operating
the processor at 166MHz clock (FSB333) while the memory is
limited to 133MHz clock (DDR266) ? You really could use
some PC2700 or faster memory, so the FSB and memory can be
operated at the same speed.
And, of course, the answer is no. This table in the manual
says if the FSB is run at 166*2=333, the memory has to be
DDR333 as well. Your memory is DDR266 (PC2100), so I guess
you are stuck at 133*2=FSB266.
TABLE 1.3.1 FSB/DDR Support Table
FSB DDR266 DDR333 DDR400
200/266 MHz Yes Yes Yes
333 MHz No Yes No
A multiplier mod would really come in handy, if you had an
older processor, but if you bought your 2500+ recently,
then changing the multiplier won't work.
Ways out of this mess, would be to find a FSB266 processor,
and the faster ones are hard to find, or buy better memory.
Neither option is cheap.
I don't know if your BIOS will allow you to overclock your
ram or not. You could try setting CAS higher and set Trcd to
one more than it is currently set to, as loosening Trcd is
supposed to expose whatever headroom a memory has to offer.
You would want to check that with memtest86, to make sure
the memory is error free. I would start with one stick of
memory, just to see if the memory is interested in
overclocking or not.
Note that your manual says the memory slots only support
two banks of double sided PC2700 memory, which means you
wouldn't be able to run all three sticks at that speed.
Buying two 512MB double sided sticks, would give you 1GB
of memory using two slots, and they could be PC2700 or
PC3200, and operate at DDR333 (faster memory is backward
compatible).
Unless you've got more money to spend, you are stuck
at 1466MHz.
It is possible this website can get you a different
multiplier - they claim to have a recipe to make an
AthlonXP into an AthlonXP-M mobile processor. This shows
some bridge cutting/bridge painting options:
http://www.ocinside.de/go_e.html?/html/workshop/socketa/tbred_painting.html
How to cut or paint a bridge (there are many sites on the
web that show techniques for doing this, to the various
models of processors):
http://www.ocinside.de/html/workshop/socketa_bridges.html
Pin/socket modding is shown here:
http://www.ocinside.de/go_e.html?/html/workshop/pinmod/amd_pinmod.html
As I'm not an AMD guide, I have no idea how all this stuff
works, so you are on your own. Searching here, for info on
"bridge modding", might be an option - use the middle search
box and click the "all terms" button for best results.
http://www.nforcershq.com/forum/search.php
Paul