D630 with 3GB ram?

I recently purchased a D630 with 1GB ram on 1 DIMM since I couldn't bring myself to pay Dell an absurd amount for a memory upgrade. I'm planning on purchasing more ram for the second slot, and was debating whether I should add 1GB or 2GBs. I know I'd forfeit the benefits of dual channel ram by opting for the 2GB, but I can't help thinking that 3GB ram would be better than 2GB ram. Am I correct in thinking this or will I see a significant decrease in performance from the lack of dual channel? Thanks.

 

Yes 3gb will offer more performance then 2gb in synchronous dual channel. Dual Channel will give you less then 10% percent peformance increase which probably wont be noticeably.


Look at the Hot Ram deals thread for great prices on DD2-667 ram.

Also i beleive the 3gb will run in asynchronous dual channel(google/search it)

 

That's what I would have thought, so I'd be inclined to go for the 3GB. However, I've seen some who have reported that 2GB (1GBX2) of synchronous ram will yield better performance. I don't know how much credence one should give to Vista's built-in performance ratings, but the guy in this link seemed to think his system would actually perform better with less ram, as long as that smaller amount was paired properly. Is that, in yours or anyone else's opinion, total crap?....I've always thought a significant increase in total ram would yield positive results.

http://episteme.arstechnica.com/eve/forums/a/tpc/f/77909774/m/159002406831

 

When you are calling it synchronous or asynchronous dual-channel you are referring to the fact that the chipset has two distinct channels, which are either used together or separately. When you are calling it single channel (in this context) you are referring to the fact that only one channel is being used, leaving the other channel unused.

In a desktop you usually have four dimm slots on the two channels provided by the chipset. If you put two matching dimms in separate banks you will have a synchronous dual-channel, which is what we commonly call dual-channel mode. If you put two matching or differing dimms in the same bank you will have a single channel configuration, leaving the other channel unused. But if you put differing dimms in separate banks you will have asynchronous dual-channel, using both channels but not at the same time, which is what we often call single channel mode.

A notebook chipset also has two channels, but since there are only two dimm slots, it is technically not possible to run a notebook in single channel mode with two dimms. As soon as a second dimm is inserted you will be using the second channel. Asynchronous dual-channel can't offer increased bandwidth as any memory fetch would target a single dimm, but it might be a slight bit better than a single channel / single dimm configuration.

As for performance, you will clearly see the difference in a memory bandwidth benchmark, but you will probably not notice it in real world performance.

 

So, if I'm getting all of this right, paired dimms would yield maximum performance, but the small performance increase of having the dimms paired as opposed to unpaired would likely not be noticeable. Either way, the laptop will utilize both channels, and having both channels filled with some sort of ram would still be slightly (but not noticeably) better than a single dimm. I'd therefore probably benefit more from the 2GB+1GB configuration with a total of 3GB since the small performance loss from the lack of synchronous dual-channel will be very minor and the benefit from the larger quantity of ram will overshadow this loss of performance. Does this sound like an accurate assessment?