Pentium 4 2.8Ghz only showing 1.4Ghz in BIOS


I have here a Intel Desktop Board D845EPI with a P4 2.8Ghz processor running on a 400Mhz bus with DDR266 RAM.

Upon boot, when the memory is testing, the processor is identified as a 2.8 P4. But from within the BIOS general screen, it shows it clocked at 1.4Ghz. This board does not allow for manual tweaking of the processor or bus speed.

From Windows system properties it also is identified as a 2.8, but the next line reads it running at 1.4Ghz.

I have updated the BIOS to the most recent version, and also reset the CMOS jumper and even taken the battery out to see if the thing would reset properly, but no dice.

Any ideas what is going on or what I can do to try to remedy this?

Thanks in advance,

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Gary CaseConnect With a Mentor RetiredCommented:
I don't think Intel made a 2.8GHz P-IV with a 400Mhz FSB.   At least it's not shown on the Intel site in their CPU lists; and the specs for that motherboard do not show support for any P-IV's above 2.6GHz with a 400Mhz FSB (they do show a 2.8GHz at 533Mhz FSB).

So the first question is what IS the CPU?   ... and is this a board that WAS running well, and has suddenly showing this problem?   ... or have you just installed a CPU in it?   If the latter, you may have installed an incompatible CPU.

If it WAS running well, please confirm exactly what CPU you have in it.
It sounds like you have an 800 MHz FSB CPU running on a 400 MHz FSB.
It's running at 1/2 speed...
Gary CaseRetiredCommented:
... that's my thought as well => just waiting for confirmation of exactly what CPU is installed :-)
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download and install everest to help properly identify the cpu.
EdeneyeAuthor Commented:
That's what I suspected, but I just couldn't believe it, since it's not a homemade rig. The owner bought it from a local computer shop.

I don't know if it just started happening or not. Obviously if the cpu and board don't mix, it's been going on forever. I will pull the processor to get the exact specs and talk to the person about it and get back to you.

EdeneyeAuthor Commented:
Hoping that using the Everest utility will spare me removing the cpu. FYI I have Hyperthreading disabled right now.

I think I id'd the motherboard incorrectly. Stamped on the pcb is Intel Desktop Board D845EPI/D845GVSR. Everest identifies it as the D845GVSR which does support the 2.8Ghz P4.

Here is some of the info that Everest has given me on the processor:

CPU Properties:
      CPU Type                                          Intel Pentium 4, 1400 MHz (14 x 100)
      CPU Alias                                         Northwood HyperThreading
      CPU Stepping                                      M0
      Instruction Set                                   x86, MMX, SSE, SSE2
      Original Clock                                    2800 MHz
      Min / Max CPU Multiplier                          14x / 14x
      Engineering Sample                                No
      L1 Trace Cache                                    12K Instructions
      L1 Data Cache                                     8 KB
      L2 Cache                                          512 KB  (On-Die, ECC, ATC, Full-Speed)

 CPUID Properties:
      CPUID Manufacturer                                GenuineIntel
      CPUID CPU Name                                    Intel(R) Pentium(R) 4 CPU 2.80GHz
      CPUID Revision                                    00000F25h
      IA Brand ID                                       09h  (Intel Pentium 4)
      Platform ID                                       0Fh  (Socket 478)
      IA CPU Serial Number                              Unknown
      Microcode Update Revision                         2B
      HTT / CMP Units                                   2 / 0

Here is the full report including motherboard information that Everest gave me:

Gary CaseRetiredCommented:
Well ... the motherboard may indeed show support for a 2.8GHz / 400MHz FSB combination;  but according to Intel's list of all the P-IV's they've made, they've never made a 400MHz FSB version of a 2.8GHz CPU:

Further, the Everest report shows that the CPU is a hyperthreading Northwood -- THAT is definitely an 800MHz FSB CPU !!

... so the issue here is exactly as I suspected and stated in my first post  => "... an incompatible CPU "   You simply have an unsupported CPU (an 800MHz FSB Northwood), which the board is running at 1/2 of its designed FSB speed.   Lucky it runs at all !!
Gary CaseRetiredCommented:
... as a follow-on thought:   r.e. "... The owner bought it from a local computer shop." ==> I think the local computer shop owes this guy, at a minimum, a 533FSB 2.8GHz CPU !! (i.e. a CPU at the speed they sold him that actually runs at that speed !!)
Actually they did make a socket 478 - 2.8 GHz P4 for a 400 MHz FSB:

.... But it has a x28 multiplier and yours is x14.
.... It also is not Hyper-Threading and yours is.

The only 2.8 GHz socket 478 CPU's that also supports Hyper-Threading were for an 800 MHz FSB.
That is also consistant with the x14 multiplier.

You have an 800 MHz FSB CPU on a 400/533 MHz FSB motherboard.
The board is defaulting to 400 MHz FSB (to the safest setting) because it can't properly accomidate the CPU's 'desired'  settings.

End result, your CPU is running at 1/2 speed.

Yup, make the dealer fix it.........

Since I had the pages open I thought I'd drill it down some more.
Only 4 or the 2.8 GHz HT skt 478's have 512k cache.
Only one of those matches the CPUID string (CPUID revision) in your report above:
You have this CPU:
EdeneyeAuthor Commented:
You were exactly right. It's a 800Mhz CPU in a 400Mhz Bus board.
The person was not too happy with the people that built it when I informed her.
We're ordering a new motherboard so she can take advantage of the entire processor.

Thanks to all.
Gary CaseRetiredCommented:
You're most welcome -- is the "local computer shop" still in business ?? [I wonder if they even realize what they did]
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