Thinkpads Forum

Is there anything wasteful or bad about having two different-sized RAM sticks in a T60 or T61 (eg. one 2G and one 1G or 0.5G) ? Assuming both sticks are the same speed. I thought someone once wrote that both sticks should be the same size.

Two identical modules will enable the system to use the memory in dual-channel mode, theoretically doubling the memory bandwidth. A pure memory bandwidth benchmark will show a big difference, but in practical terms most CPU-intensive benchmarks will show a gain of maybe 2-5% in a dual-channel configuration.

Thanks, i thought it was something like that. But I dont understand the practical implications of having two different-sized DDR2 PC5300 sticks.

Most apps ppl use would tend to be I/O-bound or swapping memory, rather than CPU-bound (i think)

So what would be better?...
a) 2x512MB (identical size)
b) 1x1GB + 1x512MB (different sizes but more RAM)

As you said, memory (availability) and I/O are the bottlenecks: more memory trumps any other improvement (with disk performance probably second). So I would suggest going for the 1.5 GB configuration, and I will be doing the same on my X61, using 1+2 GB modules for 3 GB total.

Thanks! So I will just add someone's dirt-cheap throw-away 0.5gb to the 1gb on my t60 running XP
Whereas I guess adding 2GB to 1GB is the price you pay for vista, lol

Thanks!

Just wanted to add using that (2) 'identical' modules to produce dual channel does not necessarily mean the manufacturers need to be the same. I have 1GB Elpida and 1GB Crucial in my T60 and it is definitely running dual channel.

I have a 1 and a 2g stick in mine. Unless they come up with a way to actually enable the full 4g, swapping the 1 for another 2 is too much of a waste. It works fine though

Two identical modules will enable the system to use the memory in dual-channel mode, theoretically doubling the memory bandwidth. A pure memory bandwidth benchmark will show a big difference, but in practical terms most CPU-intensive benchmarks will show a gain of maybe 2-5% in a dual-channel configuration.

With a T60 which has the 3 GByte ram limit, would putting two 2 GByte sticks in give it dual channel? Right now I have a 1 and 2 for 3 total. I still have another 1 and could go back to 2 GByte total. Would that be better or is it better to have 3 GByte with unbalanced sizes.

For most applications, 1+2 GB will likely provide better performance than 1+1 GB.