No 64 bit intel pentium 4 mobile?

[ThinkPad560X]

I got my IBM ThinkPad G40 out and started to use it again. I think I had it maxed at 2GB RAM and still has its 80GB IDE HDD. I was wanting to see of upgrading the processor to a Prescott HT as my G40 has a Northwood 2.80GHz. From what I can see in the mobile there is no 64bit processor Pentium 4M. But doesn't the G40 use a desktop processor? From CPUz: Intel Pentium 4, Northwood, Brand ID: 9, Socket 478 mPGA 2.80GHz MMX, SSE, SSE2. I just checked the CPU page again and it does have the desktop CPU 478. But from what I see Pentium 4 HT 478 doesn't support 64bit or just has N/A. I was going to try to run Windows 10 Pro 64bit on my G40.
https://en.wikipedia.org/wiki/List_of_I ... processors

[Thinkpad4by3]

Yes ,its a desktop chip and no there arent any 64-bit P4s. I dont know where you got the idea that there were any? The Core 2 Duo was the first 64 bit processor Intel made AFAIK.
Now if you could mod it to take an AMD Athlon 64 if you really want that 64 bit power

[axur-delmeria]

IIRC no Socket 478 Pentium 4's were 64-bit-- only the LGA 775 ones were.

See CPU-World: http://www.cpu-world.com/CPUs/Pentium_4 ... scott.html

[ThinkPad560X]

Yea because my ThinkCentre is a 775 Pentium 4 HT 64bit support. The Prescott did support 64bit.

[Screamer]

You will not be able to swap your Northwood for a Prescott in your G40, because of how the G40's BIOS lacks the required microcodes for Prescott. Unless, you are planning to add the microcodes by yourself?

Also, the G40's chipset does not support Hyper-Threading if you did not notice. It should be still capable of running a hyper-threaded Pentium 4, but without the Hyper-Threading capability.

Windows 10 64-bit on a G40? Tough, but it may be possible. You need a Pentium 4 HT 3.4E (SL7Q8), or a Pentium 4 HT 3.2E (SL7QB). These 2 processors have EM64T and are 64-bit capable, but are extremely rare and are nearly impossible to find. These 2 processors lack NX though, which is required for Windows 10. You also need to perform a modification on the socket to force them to run on the 533MT/s or 400MT/s bus, as the 82852GM memory controller hub does not support a front-side bus speed of 800MT/s.

Code: Select all

BSEL1 BSEL0 - Resulting Speed
[L] - [L] -> [400MT/s]
[L] - [H] -> [533MT/s]
[H] - [L] -> [800MT/s]
[H] - [H] -> [Undefined]
H = Voltage High | L = Voltage Low (on the socket)

If you truly want the real deal to run Windows 10 64-bit on your G40, and with a minor BIOS modification, you can. I can't assure you that NX is supported on the 852GM chipset, though. Might need a little modification to the processor's model specific registers to get it to work, theoretically speaking that is. The Pentium 4 2.8F (SL8JX) is the processor you need to run Windows 10 64-bit, since it supports EM64T and NX. Additionally, it does not require a BSEL modification to get it to run. This would be your best choice. It isn't.

I wish you good luck on the search for them, because they are insanely rare and difficult to find.

EDIT: Crossed out potentially misleading information.