End of the POST "Error

Try replacing the CMOS battery.

As I understand it, you tried to upgrade the CPU from 1.86GHz to a 3.00GHz. The error message is stating that the BIOS (Basic Input Output System) cannot recognise the CPU because it is not in the list of supported CPUs. You need to download an updated BIOS (if available) for the particular motherboard in your PC. You will need to get the model number of the motherboard which is usually written on the motherboard. Then go to this web site: http://www-307.ibm.com/pc/support/site.wss/homeLenovo.do

Search for an updated bios for your motherboard. There should be instructions on how to update the bios.

You have to update the BIOS

http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareIndex.jsp?lang=en&cc=us&prodNameId=316715&prodSeriesId=316713&swLang=8&taskId=135&swEnvOID=181

update your bios

Could be that the bios itself is corrupted, You could try reloading that latest bios. Update the BIOS using flash from OS. link: http://download.lenovo.com/ibmdl/pub/pc/pccbbs/thinkcentre_bios/24jy55usa.exe

You need an other BIOS driver.
Intel P6 and NetBurst micro-architecture microprocessors may contain design
defects or errors known as errata that may cause the product to deviate from
published specifications. Many times, the effects of the errata can be
avoided by implementing hardware or software work-arounds. Errata and work-
arounds are documented in the appropriate processor specification update,
which can be found at www.intel.com. Intel P6 and NetBurst micro-
architecture microprocessors include a feature called "reprogrammable
microcode", which allows certain types of errata to be worked around via
microcode updates. The microcode updates reside in the system BIOS and are
loaded into the processor by the system BIOS during Power-On Self Test, or
POST.

I suggest this is not going to work.
1.Your motherboard is supplying 1.75 DC volts of electricity to the processor socket.
You have installed either a SSpec number SL68Q, or SL62P,
Intel Pentium 4 processor. (The sSpec number is on the top of the processor case)

These Intel Pentium 4 processors use 1.425 to 1.525 DC volts of electricity. If you haven't already, you are going to burn this processor up.

Also, the Intel Pentium 4 that you had before, is based on the Willamette Core. (180nm) These earlier Pentium 4's did not have HT.
Hyperthreading Technology.

The Intel Pentium 4 you have in it now, is based on the Northwood Core. (130nm) These Pentium 4's come with HT.

Even if you could go into your BIOS Setup utility, and change the CPU voltage, and lower it, the HT in the processor you have now, wouldn't work on this motherboard.
(CPU stands for Central Processing Unit. Another name is Microprocessor, or simply -> Processor)

You won't be able to lower the voltage in BIOS Setup, for this processor. IF you did, then you would change the Front Bus Speed, and the ram memory wouldn't work.

Solution?
Obtain an Intel Pentium 4 processor, that uses the Socket 478 processor socket, has a 400MHz FSB, and is based on the Willamette Core.

Here is a list of Willamette Core, Intel Pentium 4 Microprocessors, that will work,
http://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_microprocessors#.22Willamette.22_.28180_nm.29

to use your computer you need to put back your old cpu in .
then download the upgrade, and apply i.
after your bios is updated, your new plugged processor will be reconized.

Hi cogilbert,
I had a similar problem with my PC which had older version 1 USB. I purchased a USB 2 PCI card with USB Hub, installed and problem solved. It really not a very expensive proposition. The card comes with the necessary software and drivers. It works great.
--RoadHawk