Sony Vaio PCG-K415B upgrade, what processor can my laptop take?

Good Day All.

This is my 1st post so I hope I have put this in the right place.

I owe a Sony Vaio PCG-K415B Laptop, I have had it for a number of years will no problems, a few months ago the laptop would switch on but nothing would show on the laptop screen or extrenal monitor.

I removed the SL7NX - Intel Celeron D (Socket 478) - 3.067GHz/256/533 processor.
I asked a friend to put this processor in his desktop pc for a quick test, his system powered up and went into the bios fine, so we did not try and boot into an OS, So as the processor worked in a Desktop PC i tought that it must be a problem with the laptop mainboard.

Last night I find a 2.6GHz processor, So I tought I will just slap it in the laptop and see what happens, and what you know it boots.

The laptop does not boot each time I power on or restart, but I am putting this down to running with the worng processor in it.

So now to my question, As the standard processor in this laptop is a SL7NX - Intel Celeron D (Socket 478) - 3.067GHz/256/533 processor.

What is the most powerfull processor that I can fit into this laptop.

I have just read the Service Manual, and it also has a list of other models and what processor thay come with, by the looks of the service manual they are all based on the same motherboard.
K47 - SL7NB
K45 - SL7NB
K45F - SL7NB
K43F - SL7NX
K44FP - SL7NA
K43Q - SL7NB
K415B - SL7NX

SL7NX - Intel Celeron D (Socket 478) - 3.067GHz/256/533 (1.25-1.4v)
SL7NA - Intel Mobile Pentium 4 (Socket 478) - 3.067GHz/1024/533 (1.25-1.4v)
SL7DT - Intel Mobile Pentium 4 (Socket 478) - 3.067GHz/1024/533 (1.25-1.4v)
SL7NB - Intel Mobile Pentium 4 (Socket 478) - 3.200GHz/1024/533 (1.25-1.4v)

I would like to be able to use the SL7NB, do you think this will work in my laptop?

Thanks for your time.

Best Regards.

 

Hi,
I have the same sony machine , any chance of a PDF of the service manual ?
regards Mick