Clock speed of faster processor same as old?

  Salamander7 17:01 PM 17 Mar 13

I have just replaced a Pentium 4 2.80ghz CPU with a 3.80 GHZ CPU. In System info the machine reports the new processor as Pentium 4 3.80 GHZ but the clock speed is reported as 2.89. Why??

System is a Fujitsu Siemens Scaleo P tower with a Fujitsu Siemens D 2190a mother board with Intel 915GL chipset. The BIOS is Phoenix. Win XP Home Edition.

Would a BIOS update help? I have not touched the BIOS at all so should I have entered it and changed a setting for the new CPU.

  Chronos the 2nd 17:04 PM 17 Mar 13

If you are using such an old processor that will mean that you are using an equally old motherboard and unfortunately unlike today's motherboards I would not attempt to update the BIOS unless you are extremely confident. Get it wrong and you will have a rather large place mat.

  Salamander7 17:13 PM 17 Mar 13


I am aware of this issue. Is the reason the processor is not running at its optimum speed because of the BIOS? Or is there any other cause. I could pay for a BIOS flash but would this make a difference?

  Fruit Bat /\0/\ 17:28 PM 17 Mar 13

perhaps you need to set the Bas clock and multiplier in BIOS

Base clock x CPU multiplier = CPU MHz Speed

  Salamander7 17:50 PM 17 Mar 13


Please could you illustrate your point with a simple example? I could certainly enter the BIOS and look for "base clock" but would there be a number of options for me to choose from or the invitation to get involved in some scarey calculations?

It is Phoenix BIOS and the new CPU is 3.80GHZ

  Fruit Bat /\0/\ 19:12 PM 17 Mar 13

HAve a read here

  woodchip 19:52 PM 17 Mar 13

If you can get the manual for the motherboard it should tell you what to change to get full speed from new cpu. it may be BIOS setting, or may be a Jumper on the board

  Salamander7 00:57 AM 18 Mar 13

Well I checked out my Phoenix BIOS and it wont give access to the relevant section. The BIOS believes the CPU has a clock speed of 2.80 and thee is no scope for change. I suspect a BIOS update is the only way forward.


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