RAM upgrade config question

Sorry if this has been discussed; couldn't find it in a search.

Suppose a computer comes with 512 MB of DDR2-533 (PC2-4200) RAM, upgradeable to 2 GB max, and is dual channel capable.

Suppose the RAM is in one 512 stick, with one empty slot, and I want to add some.

OK, if I got another 512 stick, the computer could run in dual channel mode which I understand is better than single. Total 1 GB

I could get a 1GB stick instead. Total 1.5 GB. But because the 2 sticks don't match, I would not get dual channel mode. Yes?

How would the two compare in terms of performance increase?

Eventually I'd like to have 2 x 1GB sticks. But at the moment I can't a) afford it b) contemplate throwing out a stick of 512. So I'm going to add right now rather than replace, just not sure what is most logical.

Thanks very much for any input.

 

you are correct...they will not run dual channel if they aren't identical. i would opt for the 1.5 gb over the 1 gig dual channel.

 

Okay, good, that makes it more efficient to add more later also. Just didn't want to buy a big stick and end up the same or slower than with the smaller one. How much dual channel makes a difference is something I'm not too clear on. Thnx ejl

 

oh, and make sure it has the same latency...though most types of ram of the same speed usually are the same latency. just another thing to double check. though to be honest, i'm not 100% sure about the dual channel business, i do believe that having more ram would be beneficial.

 

You put the same(a pair) brand, model, speed.....everything to your motherboard, it should work perfectly as long as your motherboard can support the dual channel memory, and check the BIOS to make sure the motherboard can detect the Dual channel.....

 

Thanks, I don't think I would have a problem getting it to work; I was just curious whether 512+512 would be faster than 512+1GB because the former could run in dual channel and the latter cannot.

 

I may be wrong but I think 512 + 1gb will be faster. Dual channel is nice but I prefer to have more ram. From what I know, dual channel only increases speed by less than 5%.

 

like they say, more ram is best. less loading from the HDD. and if your lappy has a slow 5400rpm HDD, chances are you wont gain much from dual channel anyway since the applications that can benefit from dual channel mode are quite hard disk intensive..