HP Pavilion ze4300 (ze4000 series) CPU upgrade

First place to check is to see if the cpu you want has been an option... Get the part number of your motherboard, see if that motherboard has been sold with the cpu you want to use. Next step is finding a bios that supports the cpu you want to use...

And the largely un-answered question is if the bios will install on your machine...

Notebooks unlike desktops, the motherboards, the bioses aren't updated... like a desktop "NON-OEM Motherboard...

A system that may have many cpu's in it over the course of it's lifetime... the NON-OEM motherboard mfg's providing bios updates...

http://www.partsurfer.hp.com/cgi-bin/spi/main

PS: You don't state the amount of ram installed..... Max it out... that may be the "best" bang for the buck.

When buying ram look for ram that if that lappy was to die tommorrow you could use it in something else....

On the bios, don't count on it being updated... If they didn't sell it with that CPU, I doubt you're going to find a bios that works. On the part number of the motherboard, when you go to partsurfer, type in your model, sub-model it will give the listing of what motherboards and cpu's have "offically" been used in that machine... Hp most of the time have a de-featured motherboard, and a "full-featured" one... Full featured with all the options and taking the faster cpu I believe. You may be able to use this program to probe, addtionally if you press F10? / or was it F11 at boot you will see some info during the post. Unknown Device Identifier 5.02 Freeware Unknown Device Identifier enables you to identify the yellow question mark labeled Unknown Devices in Device Manager. And reports you a detailed summary for the manufacturer name, OEM name, device type, device model and even the exact name of the unknown devices. With the collected information, you might contact your hardware manufacturer for support or search the Internet for the corresponding driver with a simple click. With this utility, you might immediately convert your unidentified unknown devices into identified known devices and find proper driver on the Internet and contact the hardware device manufacturer or vender. Known devices recognized by Microsoft Windows will also be analyzed independent of the operating system. http://www.zhangduo.com/udi.html

Post back if you get it to working. Some have reported (forget the model numbers) that even after they applied the bios that was supposed to provide support, and used the correct cpu it was a no go, either that or the bios wouldn't install... I forget... May be the people just didn't do it in the proper order.... Seems to me "if" the motherboard is the correct part number, and the correct bios is applied along with a supported cpu it should work... Unless HP is writing some kind of code into the bios installer that looks for certain info, before it installs...