OT: fsb / ddrII settings ?

  • Thread starter Thread starter RJK
  • Start date Start date
R

RJK

Lost again over actual board mhz / ddr mhz / and quad pumping etc. !

Asrock NF6G-VSTA motherboard - landed up with 2x 512mb ddr2-667 memory in it
and a x2 5600 2x2.8ghz Windsor cpu.

Motherboard bios cpu "overclock" mode set to "Auto" = CPU freq. is greyed
out at 200, and PCIE freq. greyed out at 100
....motherboard bios memory clock is set to 333mhz (DDRII667) ...166mhz
actual running speed on the board ?

CPU-Z v1.43 reports:- (whilst making the cpu do something e.g. cpu burn in
with Hot CPU Tester Pro 4 - cpu burn in)

CPU-Z cpu tab:-
Core Speed 2812.9
multiplier x14.0
Bus Speed 200.9 mhz
HT Link 803.7 mhz
....and
CPU-Z Memory tab:-
DRAM freq. 312.5mhz
FSB:DRAM CPU/9

With cpu NOT under load and AMD's "Cool'n'Quiet" has reduced settings to:-
CPU-Z cpu tab:-
Core Speed 1004.6
multiplier x5.0
Bus Speed 200.9 mhz
HT Link 803.7 mhz
....and
CPU-Z Memory tab:-
DRAM freq. 200.9mhz
FSB:DRAM CPU/5

i.e. under the CPU-Z "CPU" tab, Bus speed remains the same when cpu is
running at 1ghz or 2.8ghz but,
under the CPU-Z "Memory" tab DRAM freq. changes from 200.9 mhz to 312.5 mhz
, and of course the ratio changes from /5 to /9 respectively.

i.e. Why does Bus speed, under the cpu tab remain the same ?

....am I missing something here ?

....any thoughts gratefully accepted !

TIA

regards, Richard
 
RJK said:
Lost again over actual board mhz / ddr mhz / and quad pumping etc. !

Asrock NF6G-VSTA motherboard - landed up with 2x 512mb ddr2-667 memory in it
and a x2 5600 2x2.8ghz Windsor cpu.

Motherboard bios cpu "overclock" mode set to "Auto" = CPU freq. is greyed
out at 200, and PCIE freq. greyed out at 100
...motherboard bios memory clock is set to 333mhz (DDRII667) ...166mhz
actual running speed on the board ?

CPU-Z v1.43 reports:- (whilst making the cpu do something e.g. cpu burn in
with Hot CPU Tester Pro 4 - cpu burn in)

CPU-Z cpu tab:-
Core Speed 2812.9
multiplier x14.0
Bus Speed 200.9 mhz
HT Link 803.7 mhz
...and
CPU-Z Memory tab:-
DRAM freq. 312.5mhz
FSB:DRAM CPU/9

With cpu NOT under load and AMD's "Cool'n'Quiet" has reduced settings to:-
CPU-Z cpu tab:-
Core Speed 1004.6
multiplier x5.0
Bus Speed 200.9 mhz
HT Link 803.7 mhz
...and
CPU-Z Memory tab:-
DRAM freq. 200.9mhz
FSB:DRAM CPU/5

i.e. under the CPU-Z "CPU" tab, Bus speed remains the same when cpu is
running at 1ghz or 2.8ghz but,
under the CPU-Z "Memory" tab DRAM freq. changes from 200.9 mhz to 312.5 mhz
, and of course the ratio changes from /5 to /9 respectively.

i.e. Why does Bus speed, under the cpu tab remain the same ?

...am I missing something here ?

...any thoughts gratefully accepted !

TIA

regards, Richard
Click to expand...

That is not the bus speed, that is the (200MHz) input clock signal to the CPU.
It comes from the clock generator. There are programs like SETFSB that
can change that value, but when SETFSB or ClockGen change the clock,
they tend to do it slowly. Perhaps too slowly as a power management
tool. FID/VID changes on the other hand, are down in the 50 microsecond
range, so change rapidly (the number of changes per second is small, but
the transition time to make the change is rapid).

The other clocks in the processor, are based from the input clock signal.
Using PLL clock synthesis, the other clocks are a multiple in frequency,
of the input clock. So a PLL multiplies the 200MHz clock by 14 to get
you a core clock of 2.8GHz.

The PLL synthesis has to be specially designed, to make the fast transition
and remain locked.

http://www.freepatentsonline.com/6914490.html

The "Feedback Frequency Divider" in the diagram in that patent, is the equivalent
of your "multiplier" of 14. Changing the "Feedback Frequency Divider" register
value is what changes the core frequency.

http://www.freepatentsonline.com/6914490-0-large.jpg

Best guess,
Paul
 
That is not the bus speed, that is the (200MHz) input clock signal to theCPU.
It comes from the clock generator. There are programs like SETFSB that
can change that value, but when SETFSB or ClockGen change the clock,
they tend to do it slowly. Perhaps too slowly as a power management
tool. FID/VID changes on the other hand, are down in the 50 microsecond
range, so change rapidly (the number of changes per second is small, but
the transition time to make the change is rapid).

The other clocks in the processor, are based from the input clock signal.
Using PLL clock synthesis, the other clocks are a multiple in frequency,
of the input clock. So a PLL multiplies the 200MHz clock by 14 to get
you a core clock of 2.8GHz.

The PLL synthesis has to be specially designed, to make the fast transition
and remain locked.

http://www.freepatentsonline.com/6914490.html

The "Feedback Frequency Divider" in the diagram in that patent, is the equivalent
of your "multiplier" of 14. Changing the "Feedback Frequency Divider" register
value is what changes the core frequency.

http://www.freepatentsonline.com/6914490-0-large.jpg

Best guess,
    Paul- Hide quoted text -

- Show quoted text -
Click to expand...

Many thanks,
(here I am again on Google NG's i.e. NNTP for OE6 - tried port 443 as
well as the usual 119 !)
....anyhow, ...not being happy with 166mhz memory, for some strange
reason ;-)
i.e. seeing as that bios screen "AUTO" setting appears to fix bus
speed to 200mhz - I suppose I could have wound it down to 166mhz
synchronous to match the board speed of those ddr2-667/5300?
modules ?
....then I started wondering if Cool'n'Quiet would still work ...so
many permutations and reboots to find out what's happening !

- I seem to have pulled it out and fitted 2x1gb pc2-6400/ddr2-800
200mhz actual board speed memory? ...phew!

Now, when thrashing the cpu, CPU-Z "Memory" tab reports DRAM Freq.
401.8 mhz. At idle 200.9 mhz.
....so I suspect that translates to 200mhz and 100mhz actual memory
frequencies on the board !)
....(and if so - memory speeds haven't changed much, down on the ground
e,g, since 168pin SDRAM 100mhz and PC133 etc. - have they ?
Core speeds 2812.9mhz (x14.0) and 1004.6 mhz
(x5.0) ...respectively. ...and as you say - bus speed stays at
200.9mhz

A worthwhile procedure if only because whilst swapping out memory, I
spotted VF700-AlCu on gpu card not secure enough ! (fortunately I left
Speedfan4.34 running an notice the temp. climbing!),
....and CPU-Z / SPD chip on those OCZ2P800R21G memory modules reporting
that for 400mhz use, I should use 5.0/5/5/15/23 1.8v whilst according
to
http://www.ocztechnology.com/products/memory/ocz_ddr2_pc2_6400_platinum_revision_2
OCZ2P800R21G's can be set to "CL 4-4-4-15 (CAS-TRCD-TRP-TRAS)" 1.9 -
2.1 Volts.

....I've chosen "High" = 1.9volts and 4-4-4-15 and all seems very
stable :-)

A final thought occurs to me in that "Dual Channel" is just the
"old" / re-marketed page/bank interleave / switching feature, ...which
does of course provide quite an improvement !

regards, Richard
 
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