Thinkpads Forum

I have T60 (1951) with 2 GB memory (1GB + 1GB modules). So I need replace another module to 2GB module, but which one? Does it matter?

Does hardware work as fast with 1GB + 1GB modules and 1GB + 2GB modules?
(of course both are DDR2-667 modules)


http://www.ec.kingston.com/ecom/configu ... it1=Search

When you have two modules installed, the system runs in the so called dual channel mode. If both have equal capacity, it´s called symmetrical dual channel mode, if they have different sizes, it´s called asymmetrical dual channel mode. Now, having this said, the only differences that occur come mostly from synthetic benchmarks (like memory-intensive mathematical algorithms), there is no real-life performance. What these synthetic benchmarks show is following: symmetrical dual channel gives additional 10% system performance in memory-intensive tasks over non-dual-channel configuration, while asymmetrical dual channel delivers about 8% performance boos in memory-intensive tasks. That´t for the dual channel. The other thing that counts is the actual amount of system memory. If you plan to install Vista or Win 7 on that same machine, it is definitely recommended to install as much RAM as possible because Vista and Win 7 can better utilize more available system memory. As for XP, 2 GBs are pretty enough. In that case, it depends really on what applications you run: for example, applications like Matlab, Autocad, Maya, 3dsMax, Photoshop can benefit from additional system memory.

Hope this helps

Marin

And it doesn't matter which socket the 2Gb chip is in.

Thanks for Your excellent answer

1GB + empty = non dual channel mode
1GB + 1GB = symmetrical dual channel mode: +10% speed over non dual channel
1GB + 2GB = asymmetrical dual channel mode: "only" +8% speed over non dual channel

Am I right? So memory is little bit slower 1+2 configuration?
I suppose it's most important there are not empty memory bank?

I'm graphical designer and I use intensively CorelDraw and Photoshop. Other programs are OpenOffice, Firefox, Thunderbird ...

Corel and Photoshop files are quite big and I have lot of disk traffic and I think bigger disk cache is better too.

By the way... what are memory-intensive programs for example?

missee wrote:Thanks for Your excellent answer

1GB + empty = non dual channel mode
1GB + 1GB = symmetrical dual channel mode: +10% speed over non dual channel
1GB + 2GB = asymmetrical dual channel mode: "only" +8% speed over non dual channel

Am I right? So memory is little bit slower 1+2 configuration?

Exactly! But as you see the difference is marginal. I think for your purposes (Photoshop, Corel) you will benefit much more from the greater amount of system memory than from the type of dual channel mode

Marin

Marin85 wrote: Exactly! But as you see the difference is marginal.

I think so too, difference (+8% or +10%) is just marginal.

Yesterday I noticed, memory is much cheaper now. I paid about 60e for 1GB Kingston module 1,5 years ago. Now this same module costs only 13e and 2GB module only 23e. And it is same web-shop. Enjoy

Can i mix memories from diferent producers and still have (asymmetrical) dual channel mode?
Or it will definitely not work out?

I have already 1GB in my T60 1951WP8,
(Elpida DDR2 667 5-5-5-15-21, EBE11UD8AGSA-6E-E, orginally from Lenovo)
and i want to improve it with KTL-TP667/2G Kingston.

Regards
Mike

hrupek wrote:Can i mix memories from diferent producers and still have (asymmetrical) dual channel mode?

Yes, you can do that. But I would recommend you to test it after you upgrade to make sure they are in fact compatible (but it should be ok). Also, please note that frequency and latencies should be the same for both modules.

Hope this helps

Marin