"NRS" said:
Right on Target:
The FSB is running at 133
The Multiplier is locked at x12.
The Core Voltage is 1.26V but I moved it to 1.3 to get rid of the
Hardware alert on boot and it runs smooth.
Paul are you saying I basically can't use this thing in a P4PE because
of the 133 Bus yielding such a slow clock?
Yes. I forgot to mention that in a FSB400 or FSB533 motherboard,
the thing is pretty useless. At least the P4PE has an overclocking
option, where you can use a 200Mhz CPU clock, then place one stick
only, of DDR400 double sided RAM in slot 1. But 200 x 12 = 2.4GHz,
and I expect that would be pretty disappointing. As I understand it,
the P4PE won't do an ounce over 200MHz clock, so I don't think
you can get to 3GHz by overclocking on that motherboard. If you
are happy with a cool-running 2.4GHz processor, then by all means
use it.
A FSB800 motherboard, like the P4C800-E Deluxe, can go to FSB1200.
You can use two sticks of DDR600 RAM in dual channel, on the
P4C800-E, with a 1:1 RAM ratio, or if you only have DDR400 RAM,
you can crank the ram divider down to 3:2 ratio.
The way your mobile processor works, it has two multiplier values.
The x12 is the starting value, and considering the nominal
rating your processor has got, of 3.06GHz at FSB533, the "working"
multiplier is 3.06/0.133 = x23.
The datasheet for your processor is here. I've copied the text
for the Speedstep thing, that allows switching from x12 to x23.
http://www.intel.com/design/mobile/datashts/25302804.pdf
"Enhanced Intel SpeedStep Technology
The mobile Intel Pentium 4 processor, when used in conjunction with
the requisite Intel SpeedStep technology applet or its equivalent,
supports Enhanced Intel SpeedStep technology. Enhanced Intel
SpeedStep technology allows the processor to switch between two
core frequencies automatically based on CPU demand, without having
to reset the processor or change the FSB frequency. The processor
has two bus ratios and voltages programmed into it instead of one
and the GHI# signal controls which bus ratio and voltage is used.
After reset, the processor will start in the lower of its two core
frequencies, the Battery Optimized mode. An operating mode
transition to the high core frequency can be made by setting GHI#
low, putting the processor into the Deep Sleep state, regulating
to the new VID output, and returning to the Normal state. This puts
the processor into the high core frequency, or Maximum Performance
mode. Going through these steps with GHI# set high, transitions the
processor back to the low core frequency operating mode. The
processor will drive the VID[4:0] pins with the VID of the current
operating mode and the system logic is required to regulate the core
voltage within specification for the driven VID."
Now, on a desktop board, the GHI# and DPSLP# signals are called
TESTHI11 and TESTHI12. According to some Intel info, recommended
practice on a desktop board, is to short those two signals together
and connect them via a pullup to VCC. For perfect flexibility,
those two signals should be separated. If the DPSLP# and GHI# signals
go low at the same time, DPSLP# could sample a value of logic 1
on the GHI# signal, which would continue to request the x12 multiplier.
If the two signals were separated, you could set GHI# to logic zero
separately, then cause DPSLP# to transition low, and the new value of
GHI# would be sampled. I think these signals are driven by the
mobile chipset, but you could fake it with a couple of switches
connected to ground. The hard part will be figuring out whether
TESTHI11 and TESTHI12 are shorted together, and whether they can
be separated or not.
http://groups.google.ca/group/alt.c..._frm/thread/32b31feb6c4beca6/1da7bf9d0bc50989
I suppose another option, would be to place plastic sleeving
over the GHI# and DPSLP# pins on the processor, so they cannot
contact the socket. Then run thin insulated wire from those two
pins, outside the socket area. Then, you would place separate pullup
resistors on them to VCC, your two switches to ground, and "command"
the mobile processor to change states.
As to why I'm suggesting the P4C800-E motherboard, the 875 Northbridge
is the only one I trust to go to FSB1200. The 865PE motherboards,
like the P4P800 family, sometimes have video artifact problems at
high overclock, so would not be my first choice for a mobile P4
experiment. If you can get a P4P800 with an early serial number
(just after the P4P/P4C boards were released), the 865PE Northbridges
on those boards work just as good as an 875. The 865PE's got crappy
after Intel had time to properly bin them by operating speed.
So, your options are:
1) 2.4GHz via setting the clock to max on P4PE.
2) 3.06GHz on P4PE, via following the appropriate sequence of steps
on the GHI# and DPSLP# signals. The CPU clock must remain at
133MHz while you are doing that (you don't want a surprise, if
the clock is set to 200MHz, and suddenly the multiplier is x23!).
Normally GHI# and DPSLP# are high (via their pullups). Ground GHI#
via a switch to ground. Next ground DPSLP# momentarily. When
the switch is open again, and the separate pullup on DPSLP# pulls
it high, the processor should be x23 and awake. Return GHI# to
logic 1 by opening its switch, ready for the next boot cycle.
3) Purchase a P4C800-E and set the clock to 300MHz. Use 3:2 RAM
ratio (DDR266 setting) for some DDR400 RAM, and it will be run
at exactly DDR400 rates. Set AGP/PCI clock speed manually to
66.66/33.33 MHz setting, to ensure the hub clock stays at 66Mhz.
HTH,
Paul
You bought a Mobile P4.