stubborn cpu speed

[mgl4evr]

hi guys!
i recently bought a pentium 4 2.8ghz, socket 478, prescott cpu.
but the thing keeps working bellow the original speed (1.8ghz, to be exact).
i have a asrock ge pro-m2 (and yes... i realize i cant expect much from an asrock...) and i:
-updated bios
-cleared cmos
-checked fsb in bios (133mhz)
-checked for "cpu stepping"
by the way, i have a 400W psu.
i'm completely out of ideas. any help is apreciated!
thanks.

mgl4evr

 

[V3NOM]

um... you actualyl bought a socket 478?

 

[GhislainG]

Your motherboard's bus is 533 Mhz and the CPU requires an 800 Mhz bus.

2.8Ghz * 533 / 800 = 1.86Ghz

 

[jimmysmitty]

What he said (above me).

The only Intel CPUs that normally had a 533MHz FSB on the 478 didn't have solid numbers.

For instance, the 2.6GHz P4 had a 400MHz FSB. But the 2.66GHz P4 had a 533MHz FSB. So you more than likely need a 800MHz FSB (200 where your 133 is) in order for it to run at full speed.

 

[mgl4evr]

thanks for the reply, guys!
the cpu costed (in your currency) about 3-4 bucks.
the bus is not 800mhz... it's 533. it says so on the cpu itself.
133*21 (bus and multiplier)=2793mhz--> 2.8GHZ
as i said in my first post, the motherboard only puts the bus at 14.
133*14=1862mhz--> 1.8ghz
as i said before, the cpu works and it's on the motherboards cpu support list.
regards...

mgl4evr

 

[GhislainG]

You are correct when you write that a P4 2.8Ghz with a bus speed of 533Mhz is available and that it should work on your motherboard. Can you change the multiplier? What does CPU-Z display for that CPU?

 

[mgl4evr]

the multiplier appears "blocked" on my motherboard.
cpu-z shows the same information as my bios.
pentium 4 2.8ghz, working at 1.8ghz with a 14x multiplier.
regards...

mgl4evr