Question about downgrading a T60 to an ULV core 2 CPU

[Glaurung-quena]

I have a T60 1952-ap2. I'm wondering if it's possible to "downgrade" it to a Low voltage or Ultra-low voltage core 2 duo (for example, a u7700 or a L7400). My goal, obviously, is a cooler laptop with better battery life. (for what it gets used for, the slower CPU speed is not much of an issue).

And no, I'm not going to buy a new laptop because I despise the gunslit screens they come with -- you'll have to pry my 4:3 screen out of my cold dead fingers.

I have googled the topic of upgrading from core to core 2 and read the posts about it in this forum. I have the latest bios and a version 3 motherboard. I know I need to find a socket M/479 PGA CPU. Fortunately they seem to be available on Ebay.

The one thing I'm not sure of is whether a lower speed FSB will work -- whether I can go from the 667 FSB it has now to a 533mhz FSB. The u7xxx CPUs have the slower 533 bus but are actually affordable, so if it's possible that's what I'll probably go with.

[Johan]

Welcome to the forum!

Your question is very interesting - but I am unable to reply with full knowledge. Anyway, the following may perhaps provide some indications about the probability. First, I looked up the specifications for your ThinkPad, and according to Lenovo.com these are the (factory) configuration:

ThinkPad T60 (1952-AP2)
Based on 1951-52U: T2400 (1.83GHz), 1 GB RAM, 60 GB 5400 rpm HD, 15" 1024x768 LCD, Intel 950, CDRW/DVD, Intel 802.11abg wireless, Bluetooth/Modem, 1Gb Ethernet, UltraNav, Secure chip, Fingerprint reader, 6c Li-Ion batt, WinXP Pro

So, you've got the T2400 Core Duo CPU (unless you have already up- or downgraded it?); its (brief) datasheet is here. Notice the specification: "VID Voltage Range = 1.1625V - 1.30V" and "FSB Speed = 667 MHz". In comparison, the Intel (brief) datasheet for the Intel Core 2 Duo U7700 CPU is here. In comparison to the T2400, notice the specification for the U7700: "VID Voltage Range = 0.800V-0.975V" and "FSB Speed = 533 MHz". If you download the full datasheet for the Intel® Core™2 Duo Processors you will read that VCCDAM= 0.8 - 1.2 V for the ultra-low voltage models (see page 33) and that VCCDAM = 1.0377-1.35 for Standard Voltage processors (see page 30) and VCCA = 1.425 - 1.575 V. For the T2400 you will find Intel Core Processors full datasheet where you, at page 28, will see that "VCCHFM = 1.1625 - 1.3 V".

I'd say that this is an indication of that the T2400 cannot be swapped by the U7700. You may use the above links to check the numbers (and the CPU package compatibility!) for the T2400 vs. the L7400.

If you want to extend your battery time, then I suggest you consider swapping your present (relatively power-hungry) mechanical HDD for a lower-power-consumption SSD.

Johan

[mariol90]

all LV/ULV processors are soldered onto a motherboard. you can see a list here: http://en.wikipedia.org/wiki/List_of_In ... processors
if the socket says "BGA" anywhere, it's soldered.

your best bet would be to get a processor with the newest stepping possible (http://en.wikipedia.org/wiki/Core_(micr ... #Steppings for list of steppings and dates), and undervolt it with rmclock or something similar. with rmclock you can also limit the processor speed, and adjust the voltages accordingly so you have a good mix of lower power and good clock speed. you could do something like get a T7400, set the multiplier to 10x (1.66 GHz) or 11x (1.83 GHz) and that should allow you to set the voltage much lower than 1.3V or whatever it uses at the stock 2.16 GHz.

edit: i see some socket ULV processors on ebay. here's some more reading on it: http://forum.notebookreview.com/hardwar ... z48gn.html mainly the 3rd post, at least.

[Glaurung-quena]

all LV/ULV processors are soldered onto a motherboard. you can see a list here: http://en.wikipedia.org/wiki/List_of_In ... processors
if the socket says "BGA" anywhere, it's soldered.

This is extremely frustrating. The wikipedia article you point to says "FCBGA6 (Socket M)" for the socket types for various ULV processors. Which would seem to suggest that it's available as both soldered (BGA) and not soldered (Socket M). Between Wikipedia seeming to say that the CPUs came in a Socket M type, and various sellers (mostly on ebay) offering them as socket M, I got the impression that they were available as such.

Then again, the only sellers who appear to be selling these CPUs as socket M types are located in China, so it could be that they don't know what they're talking about and/or are lying.

Ah well. Thanks for the tip about the voltage-reducing software. I guess I'll get a genuine socket M core 2 with a low speed and see what playing with the voltage in software can do for reducing the heat.

The Hard drive has already been upgraded to a x-25v, so that's already done.

[lead_org]

some ULV core 2 duo from china are desoldered from motherboards.