Looking for Intel Core 2 Duo Mobile T7600 2.33 GHz 667MHz FSB

[Phantomski]

Hi everyone,

I’m new here, so apologies for not posting in the right Forum.

I’m looking to upgrade a CPU in my old HP Compaq nx9420 Laptop.
It had originally Intel Core Duo T2600 2.16GHz, 667MHz FSB, 32bit.
I would like to use Intel Core 2 Duo T7600 2.33GHz, 667MHz FSB, 64bit.

The reason is not just faster speed, but mainly 64bit (latest Linux distros). With 4GB memory and SSD drive, it’s still surprisingly useful device I’m just not keen to throw away yet.

According to all the specs I could dig out it should be compatible. The chipset is i945PM rev 03. It is Socket 479 / Socket M. BIOS is the latest F.1D (68YAF) from 07/11/08 which had latest Intel CPUs support added at that time.

I have bought 2 individual CPUs from various eBay sellers for about £25, both China, as no one else had them. None of them worked. I have tested the memory and it’s all OK, the old CPU when returned back works too, but the T7600 doesn’t, it just won’t even boot, charging LED blinking 8 times (which I couldn’t find in official manuals what might mean specifically).

Now I am not a massive fan of Chinese sellers, I’ve had my fair share of counterfeit or outright deceitful products in the past. The CPUs look genuine, but I have no way of telling (no other laptop to test them), hence the suspicion.

So I would like to ask - is there anyone who would be able / willing to:
1) Test if those CPUs work (I’m living in West Sussex, so ideally somewhere in person)
2) Sell a tested and truly functional example, ideally with a chance to try it first to avoid another disappointment?

Anyone able to help or open up some old unused laptop?

Or am I barking at the wrong tree and it’s just not compatible?

 

[Phantomski]

That would be a great shame.

Just in case someone would be able to tell:
HP Model 309F / KBC Version 54.3C
NB Intel i945PM Rev. 03
SB Intel 82801GHM(ICH7-M/U) Rev. A1

 

[Phantomski]

You are moving from a 32 bit OS to a 64 and that might require some BIOS settings to be changed. I’d also look at the pins to make they are not damaged or bent, and make sure it’s not a naked Pentium 478.

A open built some socket 479 desktop boards that take SODIMMs. It might be worth looking on eBay for one of those to test. The i945 and i975 are two chipsets/models that sting to mind. I also seem to remember ASUS dipping it’s toe in 479 pool. Maybe try finding one of those.

Thanks. The latest BIOS declares it supports latest Intel CPUs for that socket, including 64bit. There’s nothing that can be changed there in terms of the usual CPU/Memory stuff like on desktop MBs - it’s just peripherals, etc., like every laptop BIOS.

Good idea with having some MBs to test the CPU, I just wanted to avoid the extra cost and try it somewhere first. Either my CPUs in another MB/laptop or a confirmed working CPU in my Laptop.

 

[Phantomski]

From what I can remember, the i945PM chipset limits you regardless of your cpu to 3GB of ram. I have both a toshiba satellite P100 with a T2300 (32bit) and an HP/Compaq NC6400 with a T7200 (64bit). I'm sure I tried both laptops with 4GB of ram installed and neither could address over 3GB even though the T7200 is 64 bit and had a 64bit OS installed.

Since this was a long time ago and I'm not 100% certain anymore I will recheck it as I still have both laptops.

That in general wouldn’t be such a problem, still better than original 2GB. But this limitation specifically was mentioned as a problem with 32bit CPU and not a problem with 64bit CPU (Intel’s own datasheets). As the Memory Controller has 64bit data interface for each channel, it’s basically just a CPU’s addressing I believe.

 

[Phantomski]

If you look on auction sites you can find places that did custom bioses to support faster chips. I got one for an older wolfdale system I had a long time ago.

Thanks, will have a look.

 

[Phantomski]

The cpus will be genuine and likely working. c'mon no ones faking an ancient T7600 cpu and every cpu i've bought from the far east has been fine and genuine especially if they're from different sellers. It's likely your mainboard revision might be an earlier one that dosen't support that cpu. Yes 945pm can only see 3gb RAM, 965GM etc.. mostly saw over 4gb fine and i know i've run 8gb before on a few laptops.

Well I’ve seen a lot of fakes in my time. When you sell something for £30, it doesn’t cost more than £5 to manufacture something that looks like a CPU with absolutely nothing on the die. Another problem with T7600 is that it was kinda rare in its time, coming late to market and quickly superseded.

But suspicions aside, let’s consider the CPU is fine, but there’s a problem with BIOS or MB.

As for MB, I find it difficult to understand how a block standard Intel chipset would be downgraded by MB manufacturer below Intel’s specs. Is there something I’m missing and it would be a common practice? Is it realistic to try to find a more recent MB revision? (quite happy to rebuild the laptop with a new one).

As for BIOS - as suggested by @Scougar I’ll have a look.

I know this is all probably a bit too much hassle for something that would be normally destined to a bin, but I think the old lappy still deserves a new lease of life. Even at 32bit/3.6GB it still works pretty well on Win10 and Ubuntu.

 

[Phantomski]

Just a heads up re compatibility. There’s the same Laptop, with T7600 in it and 4GB, all working well:
https://browser.geekbench.com/geekbench3/4322041

 

[Phantomski]

This is a very old, obsolete and slow system - what is the reason you want to keep trying to work with it?

Well, even with the old CPU it works reasonably well in both Win 10 and Ubuntu 19. For general Office and Internet stuff it’s perfectly fine. I’m also using it for coding (Microcontrollers), SDR Radio and remote management (Network, SSH, Linux, Servers, etc). It has a pretty good 17” display and full size keyboard, so despite being old and dated, it’s still very usable piece of hardware. I just don’t like chucking stuff out of the window unnecessarily. I (or others in the family) can use my other more powerful laptops and/or tablets for more demanding tasks, while I can still happily work on this one.

Only missing thing is the 64bit - for the latest Ubuntu, Mint and some SW I use.

 

[Phantomski]

The only real counterfeits i've come across in recent times are cpus with IHS that were swapped some with die underneath and some without, with the amount of E waste china probably has/gets i'd bet T7600s while rare might not be as short supplied as you may think. I got one 1 week ago for a Pentium M retro ITX (rarer than a T7600 lol) build for 98se (AGP and all!) in a modded node 202, works fine. My only guess with older revisions of boards is that the power delivery may not cope with the later chips so any BIOS update may block the microcode from being flashed. There is also a possibility the chips are not fake but just defective. If you can get them tested elsewhere maybe a refund case is in order?

Yep, I think refund will be in order. I just wanted to make sure they’re defective/fake first, but I don’t have any other MB to try it in.

 

[Phantomski]

So, just to give you an update - I did eventually get a refund from the Chinese seller. The reason? One of the guys on BIOS Mod forum asked for photos of both CPUs I had (one I’ve received as ordered, second they’ve sent as a replacement when the 1st didn’t work, claiming it’s from different source). And guess what - BOTH of the CPUs had a same serial number. I can’t believe I haven’t spotted this! So obviously either one or both are fakes, despite what they’ve been originally saying. Hard to believe I know, but there you go @Justintime . This seller has almost 100% positive rating and hundreds of CPUs sold on profile...
Upon receipt of the photos they’ve refunded the money straight away and didn’t even ask for a return.

Anyway, I’ve ordered a new one from different seller and that one worked first time without any issues whatsoever.

Many thanks to everyone who chipped in, all is sorted now and good old nx9420 is now happily humming at max available config
- Intel Core 2 Duo Mobile T7600 64bit 2.33GHz
- 4GB DDR2 PC2-5300 (667 FSB) - yes @Kei only 3.37 are addressable
- 512GB Crucial SATA SSD
- Win 10 64bit and Ubuntu 20.10 64bit

Happy days.

Btw, BIOS was not an issue, all worked even on old version.

 

[Phantomski]

great result. Hard to imagine why people feel the need to fake old CPUs like that....my guess is people order them and when they don't work they probably give up!

Yep, I think that’s the case. Just the thought of sending them back - for the £30 it’s not really worth the hassle. Nice little income stream using some old scrap. ********.