Thinkpads Forum

I just picked up a 14" T60p. Well powered with a T7600.

In reviewing the installed parts I noticed that the memory is PC2-4200. I thought that was odd since my T43p was specd with this memory speed. I checked the online parts list and sure enough that is what memory it says it has.

How could this be?

Brad

cost and availability.   the module(s) could have been left over from from an older model or, if one or more of the modules are 2GB, it's because PC2-4200 was the fastest 2GB module available for a long time.

PC2-4200 will work fine in your T60p but PC2-5300 would obviously be faster.

Thanks Erik.

Makes sense.

They are dated September 2007 the same time the ThinkPad was made.

Brad

what size are the modules, 2GB?

Yes. 1 X 2GB.

Brad

Brad wrote:Yes. 1 X 2GB.

That explains it. 2GB PC2-4200 SODIMM was introduced first and for a while there were no 2GB PC2-5300 sticks. Even after PC2-5300 SODIMMs were released, they were much more expensive than the PC2-4200 ones, something like $600 per stick versus $400. Then they dropped over 90% in value over the last year, so now everyone can afford 2GB PC2-5300 and no longer need to compromise with slower sticks.

Availability of fast DRAM is related to new wafer capacity. It takes sixteen 1Gb (gigabit) DRAM to make a 2GB (gigabyte) SODIMM or eight 2Gb DRAM.

1Gb DRAM use 65nM (nanometer) wafer fab and 2Gb probably takes 55nM and below. Each new wafer fab cost about $2B.

When there are 16 devices on the SODIMM, the input capacitance is too large to achieve higher speed. In Ohm's Law, capacitance affects the leading edge of the signal. Higher capacitance makes the edge rounder and lengthens the signal. This affect the Address bus the most and to a lesser extend Data bus.

So in the beginning, only the manufacturers who have the newer fabs can make the 2GB SODIMMs. They in turn makes the most money by charging the early adapters (consumer).

Is there a way to tell what kind of ram I have in my T60 (whether or not it has 2x 512mb sticks or 1 stick of 1gig) without tearing the computer apart?

I have checked the lenovo website using my serial # and model # but it only states that I have 1 gig in total....and not a specific breakdown of 1dimm versus 2 dimms.

Thanks,
James

Install PC Wizard.

Thanks for all the information. I just thought that in September of last year 2gb PC2-5300 were fairly available and affordable.

You could also use CPUID. You don't even have to install the program you could just run it from a USB key or from the hard drive for the memory information.

Thanks again,

Brad

Brad wrote:I just thought that in September of last year 2gb PC2-5300 were fairly available and affordable.

But they were still very expensive on Lenovo's site in Sep 2007, so I think Lenovo was still offering 2GB PC2-4200 as a more affordable alternative.

And by mid Dec 07 the price had really dropped on these PC 5300 2 GB modules.