P3B-F undocumented multiplier jumper settings - running PIII 1000/133 @ 1000/100

  • Thread starter Thread starter GreyHound
  • Start date Start date
G

GreyHound

Hi,
Is this possible to run PIII CPU 1000/133 at 1000/100? Does anyone
have undocumented multiplier dip switch settings to lock it in 10x.

BTW: I've tried running 1000/133 but it crashes upon booting OS
(Linux, Windows, FreeBSD).

I am currently running at 7.5x100 = 750MHz, but it seems like a waste
for this CPU
I am not afraid of hardware mods - so soldering jumper wires is an
option as long as I could get this CPU to run 1000/100 (core/FSB) MHz.

Regards,
GH(franz)
 
GreyHound said:
Hi,
Is this possible to run PIII CPU 1000/133 at 1000/100? Does anyone
have undocumented multiplier dip switch settings to lock it in 10x.

BTW: I've tried running 1000/133 but it crashes upon booting OS
(Linux, Windows, FreeBSD).

I am currently running at 7.5x100 = 750MHz, but it seems like a waste
for this CPU
I am not afraid of hardware mods - so soldering jumper wires is an
option as long as I could get this CPU to run 1000/100 (core/FSB) MHz.
Click to expand...

There are indeed undocumented jumper settings for larger multipliers -
above 8 or so they are simply remapped to the lowest settings. However,
these will only do anything with unlocked engeneering samples, all
retail intel cpus since early P2 days are completely multiplier locked
and no amount of tinkering will make the cpu run at other multipliers.
P3B-f boards have a quite good chance of working stable at 133Mhz FSB,
if it doesn't it could be your ram (if it's only pc100), or the agp
graphic card which might not like 89Mhz AGP clock.

Roland
 
Roland Scheidegger said:
There are indeed undocumented jumper settings for larger multipliers -
above 8 or so they are simply remapped to the lowest settings. However,
these will only do anything with unlocked engeneering samples, all
retail intel cpus since early P2 days are completely multiplier locked
and no amount of tinkering will make the cpu run at other multipliers.
P3B-f boards have a quite good chance of working stable at 133Mhz FSB,
if it doesn't it could be your ram (if it's only pc100), or the agp
graphic card which might not like 89Mhz AGP clock.

Roland
Click to expand...

Some more discussion the version of the board may also come into it is
version 1.04 should do 133 fine the older versions may not.

http://www.abxzone.com/forums/showthread.php?t=72946
 
GreyHound said:
Hi,
Is this possible to run PIII CPU 1000/133 at 1000/100? Does anyone
have undocumented multiplier dip switch settings to lock it in 10x.

BTW: I've tried running 1000/133 but it crashes upon booting OS
(Linux, Windows, FreeBSD).

I am currently running at 7.5x100 = 750MHz, but it seems like a waste
for this CPU
I am not afraid of hardware mods - so soldering jumper wires is an
option as long as I could get this CPU to run 1000/100 (core/FSB) MHz.

Regards,
GH(franz)
Click to expand...

Can't be done on that CPU - normal Intel CPUs (i.e. not engineering
sample, etc.) are multiplier locked. Motherboards often provide BIOS or
jumper settings to control the multiplier, but if the CPU is multiplier
locked, these do nothing.
 
Thanks for all suggestions.
I guess the SDRAM modules seem to be stopping me from running this
set-up @ 133MHz FSB, but I am not going to swap them out, I got
4x256MB = 1GB of total RAM running rock steady @ 100MHz FSB; I'll live
with the CPU running 750/100 instead of 1000/133.

Thanks again,
GH
 
GreyHound said:
Thanks for all suggestions.
I guess the SDRAM modules seem to be stopping me from running this
set-up @ 133MHz FSB, but I am not going to swap them out, I got
4x256MB = 1GB of total RAM running rock steady @ 100MHz FSB; I'll live
with the CPU running 750/100 instead of 1000/133.

Thanks again,
GH
Click to expand...

Assuming you have PC100 SDRAM, I suspect you've reached the correct
conclusion regarding operation at 133Mhz FSB - so why not explore the
limitations of your existing memory?

The P3B-F supports numerous FSB settings between 100 and 133, and it's
likely you can find one that provides a noticeable performance
improvement without compromising stability.

P2B
 
Hi,
I was just tired, when I did BIOS set-up. I missed the following
setting of FSB option --> 133/33. 133/43 was actually causing
problems with one of the PCI cards. Memory is rock solid at 133MHz -
eveno though the timing setting were re-adjusted to maximum available
values 3-3....-8 it works beautiful.

/GH
 
GreyHound said:
Hi,
I was just tired, when I did BIOS set-up. I missed the following
setting of FSB option --> 133/33. 133/43 was actually causing
problems with one of the PCI cards. Memory is rock solid at 133MHz -
eveno though the timing setting were re-adjusted to maximum available
values 3-3....-8 it works beautiful.

/GH
Click to expand...

Sweet :-)

43Mhz PCI is pretty much guaranteed to cause grief. I still wonder what
Asus was thinking when they put 133Mhz-capable clock generators on later
versions of the P2B series, but only provided the 133/43 setting - a
soldering iron and good eyes are required to enable 133/33.

P2B

http://tipperlinne.com/p2bmod
 
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