Thinkpads Forum

My CPU is T7250

LENOVO 6459CTO
Chipset: Intel PM965


Is the maximum supported memory supposed to be 4GB due to the limit of the mother board?




....

Disclaimer: I just ordered a T61, but haven't gotten it yet. I have, however, spent the past week or so of my life exhaustively researching it

From what I've read, Lenovo never bothered to officially certify any 4-gig SoDIMMs because they didn't exist back when it was an active product, but any 667-MHz PC5300 DDR2 4-gig SoDimm that exists today should probably work. If you read the reviews at the new egg-like site we all love, I remember seeing at least one 2x4 pair with a review that explicitly said it worked on his T61. I think it was even the cheapest one.

Interestingly, the cheapest 2x4 pair I saw there was ~$160, but the cheapest individual 4-gig 667Mhz DDR2 SoDIMM was only $70. If you can live with asymmetric dual-channel (assuming the controller even notices that they aren't an officially matched pair), it might be an easy way to save $20.

Assuming compatibility follows the usual pattern, the REAL grief is going to start about a year from now, when 667MHz PC5300 DDR2 4-gig SoDimms cost about as much as they do now (maybe MORE), but 4-gig 800Mhz DDR2 SoDimms (built with newer, higher-density chips) cost half as much, but won't work in a T61 because the ram controller might not know how to deal with a SoDimm that has 4 gigs on a single side, or with 2 or 4 chips per side instead of 8 or 16. Unfortunately, Intel tends to make matters worse than they really HAVE to be. AMD & NVIDIA chipsets will usually make an educated guess about how the next generation or two of ram will work. Most of the time, they're right, and they end up with a chipset that's capable of working with at least SOME larger ram modules someday, even if you end up with oddities like a motherboard that can take 4 gigs as 4x1 or 2x2, but can ONLY do 8 gigs with a specific configuration of 2x4. Intel usually just draws a line in the sand and says, "it's not supported, and won't be."

IMHO, 4-gig modules compatible with the T61 are probably about as cheap right now as they're ever going to get, short of outright liquidation 10 years from now. It's not guaranteed to happen, but I can't think of a single major memory technology where it didn't end up happening eventually... the unhappy 2-4 year squeeze at the end of its life when no new ram chips are getting made at that density because all the major fabs have switched over to newer, higher-density chips, but the few that remain are all getting fought over by people trying to max out the ram on their aging computers to put off upgrading for another year or two.

$135.- on eBay for 2x4GB PC2-5300
only a few $$ more for PC2-6400.

Thanks for your research. That's cool.
I was going to ask about the compatibility of DDR2 800, since it is much cheaper.

miamicanes wrote:Disclaimer: I just ordered a T61, but haven't gotten it yet. I have, however, spent the past week or so of my life exhaustively researching it

From what I've read, Lenovo never bothered to officially certify any 4-gig SoDIMMs because they didn't exist back when it was an active product, but any 667-MHz PC5300 DDR2 4-gig SoDimm that exists today should probably work. If you read the reviews at the new egg-like site we all love, I remember seeing at least one 2x4 pair with a review that explicitly said it worked on his T61. I think it was even the cheapest one.

Interestingly, the cheapest 2x4 pair I saw there was ~$160, but the cheapest individual 4-gig 667Mhz DDR2 SoDIMM was only $70. If you can live with asymmetric dual-channel (assuming the controller even notices that they aren't an officially matched pair), it might be an easy way to save $20.

Assuming compatibility follows the usual pattern, the REAL grief is going to start about a year from now, when 667MHz PC5300 DDR2 4-gig SoDimms cost about as much as they do now (maybe MORE), but 4-gig 800Mhz DDR2 SoDimms (built with newer, higher-density chips) cost half as much, but won't work in a T61 because the ram controller might not know how to deal with a SoDimm that has 4 gigs on a single side, or with 2 or 4 chips per side instead of 8 or 16. Unfortunately, Intel tends to make matters worse than they really HAVE to be. AMD & NVIDIA chipsets will usually make an educated guess about how the next generation or two of ram will work. Most of the time, they're right, and they end up with a chipset that's capable of working with at least SOME larger ram modules someday, even if you end up with oddities like a motherboard that can take 4 gigs as 4x1 or 2x2, but can ONLY do 8 gigs with a specific configuration of 2x4. Intel usually just draws a line in the sand and says, "it's not supported, and won't be."

IMHO, 4-gig modules compatible with the T61 are probably about as cheap right now as they're ever going to get, short of outright liquidation 10 years from now. It's not guaranteed to happen, but I can't think of a single major memory technology where it didn't end up happening eventually... the unhappy 2-4 year squeeze at the end of its life when no new ram chips are getting made at that density because all the major fabs have switched over to newer, higher-density chips, but the few that remain are all getting fought over by people trying to max out the ram on their aging computers to put off upgrading for another year or two.

It seems T61 does work with DDR2 800, but almost no performance difference according to an article here:

http://www.randomprocess.ca/2007/07/30/ ... -ddr2-800/

I used two of these http://www.newegg.com/Product/Product.a ... 6820220382 no issues.

I have 8gb 800mhz and it works nicely