Going with problem heading stating ->
IBM 73P0595 motherboard > CPU Support > and previous problem statement ->
"I have updated my processor from INTEL Pentium d 820,2800mzh 1500mzh to
INTEL Pentium d 945,3400mzh....."
Let's take a look at the IBM 73P0595 motherboard specifications, first;http://www.epinions.com/specs/IBM_System_Boad_W_O_POV_10_100_73P0595_Motherboard?sb=1http://www.ebay.com/itm/Lenovo-73P0595-ThinkCentre-M50-A50-Motherboard-SOCKET-478-2-4GHz-Intel-CPU-/200870757822?pt=Motherboards&hash=item2ec4d485be
A) Socket 478 processor sockethttp://en.wikipedia.org/wiki/Socket_478
B) Intel 865G motherboard chipset,http://en.wikipedia.org/wiki/List_of_Intel_chipsets#Pentium_4_chipsets
The Intel 865G motherboard chipset DOES NOT support dual core processors.
Does NOT support an Intel Pentium D; 820 OR 945http://en.wikipedia.org/wiki/List_of_Intel_Pentium_D_microprocessors#.22Smithfield.22_.2890_nm.29http://en.wikipedia.org/wiki/List_of_Intel_Pentium_D_microprocessors#.22Presler.22_.2865_nm.29
Those two processors also use the LGA 775 processor socket.
What did you base your CPU support on?
Was it the fact that the Intel 865G motherboard chipset, will support Intel Celeron D?http://en.wikipedia.org/wiki/Celeron_D#Celeron_D
The Intel Celeron D is NOT a dual core processor,http://en.wikipedia.org/wiki/Celeron_D#Celeron_D
"The Intel Celeron D processor works with the Intel 845 and 865 chipset families.
suffix actually has no official designation, and does not indicate that
these models are dual-core.
It is used simply to distinguish this line
of Celeron from the previous, lower performing Northwood and Willamette
series, and also from the mobile series, the Celeron M......"
Not the IBM 73P0595 motherboard we're talking about?
Let's just base it on the statement that you tried to upgrade, from an Intel Pentium D820 to an Intel Pentium D945,http://www.fixya.com/support/t13549945-update_intel_pentium_d_945_procesor
What motherboard are you using?
Motherboard in a HP Compaq DC7600 Desktop PC?http://h18000.www1.hp.com/products/quickspecs/12253_div/12253_div.HTML
Scroll down to the bold subheading -> Processor and Speed
Intel Pentium D820 at 2800MegaHertz (2.8GigaHertz),
with 800MegaHertz Front Side Bus, is supported.
Probably came with your computer, huh?
Intel Pentium D945 at 3400MHz (3.4GHz), with 800MHz FSB is supported also.
This can be seen by the specifications of the motherboard chipset, also. The Intel 945G motherboard chipset,http://en.wikipedia.org/wiki/List_of_Intel_chipsets#Pentium_4.2FPentium_D.2FPentium_EE_chipsets
Scroll down to 945G in the left column. (Last one listed in chart)
Apparently you just needed the 786D family Processor Microcode Update, or did that not work out?
(How did I come up with the HP Compaq DC7600, anyway?
Did you add it in a Comment, and it has been removed, or what?