More Ram questions

I'm still trying to fully understand the 32bit Vista ram limitations. I get that it only recognizes (roughy 3.5 gigs?) so you can either install a mismatched 1 gig stick and a 2 gig stick, or install two 2 gig sticks, which it will recognize as a matched pair, correct?

Then doesn't it make the most sense to install 4 gigs to get the best performance out of your ram?

 

Vista 32-bit recognizes about 3.2 gigs of RAM but it varies through computers.

If you install 2 x 2 gigs of RAM the OS will only utilize 3.2 gigs of RAM leaving the other .8 or so useless until you get a 64-bit OS.

If you are asking if you have 4 gigs of RAM with a 32-bit OS, will it take advantage of dual-channel even though it only supports 3.2 gigs of RAM? The answer is no, it won't.

 

Mmmm... okay. I asked about the dual channel previously and was told that it would run in dual channel mode.

So if it WON'T... I will get at least as good of performance as I would with 3 gigs of unmatched ram right?

 

I'm not completely sure if it will run in Dual Channel or not, my guess is it won't.

Um...if you are asking me if you get 4 gigs of RAM, will it get at least good/better performance then 3 gigs of RAM...

yes it will be the same...unless that is of course you can run 4 gigs in Dual Channel on a 32-bit OS, then I would imagine the dual channel setup would be faster.

EDIT:I apologize for my mistake, if you get 2 x 2 gigs of RAM, It WILL run in Dual Channel but only about 3.2 gigs will be available for use, my apologies.

 

Sure about that? I'd expect it to run dual-channel. I haven't tested it though.

 

I am completely forgetting things now...

I edited my post right before you posted.

 

I think it would, but it would either take .44 out of each or take a .88 out of just one

 

As long as it won't hinder performance, cool. I hope the only software I use that can't utilize 64bit Windows will change in the future.

 

Good luck with your Sager NP5790, hopefully you won't have any more issues.

By the way, did xoticpc say they were going to notify you of the problem your defective 5790 had?

 

Ooh, awesome! I can't wait for the notebook to arrive.

Lawlz, I didn't order the first one from Xotic, I ordered it directly from Sager. I had planned to to just order the replacement from them again, but after reading all the kudo's to Justin at xotic, I decided to order there, plus they were a tad cheaper.

 

Ah ic, so is Sager going to notify you of the problem it had?

 

That is one I don't know but if it takes equaly off both about 3% more bandwidth than 3GB set up. If it takes off one then the same as 3GB. this is based benches by John Ratsey posted on this forum. When you have 2 sticks in you are running dual channel even if mismatched. As stated based on those bench marks matching is fastest 3GB is 3% diff and 1 stick (single channel) 10% on Intel.

If AMD mine about 30% diff between dual and single.

I would only get 4GB if I was planning for the future and 64 bit. Price diff for 2nd 2GB stick over 1GB not worth the cost fo .2GB.

 

I don't know, they get the the laptop on Wednesday. I would like to know why it got so hot, but I don't know if they'll comment since I returned it for a refund.

 

No, they have to be identical (in size, anyway) for dualchannel to work.

 

I disagree and will try and show, Below is info pulled from SiSoft benchmrk 2GB stick notice 1 channel 64 bit and a max bandwidth of 10656MB/s

Now below is 2X1GB which we all agree is "dual channel" notice 2 channels and 2X64 bit is 128 bit which is "dual channel" and notice the the max bandwidth is now 21312MB/s

So which one is 3GB going to be? I already know but.....

Well 3GB runs w/2 channels and the max bandwidth is the same which is what dual channel is all about. On a Desktop 4 slots notebook 2. Desktops are where the confusion comes from. You do infact have to have match 2 and match the other 2 (color coded) but they do not have to match each other? Notice how this is seen above, they bank 0 and 1 match, bank 4 and 5match and just like a desktop they don't have to match each other.

The results of these benches do show matched sticks are about 3% faster than unmatched but 3GB is dual channel.

Special thanks to John R. these are his benches.

 

Your 3GB setup is matched too. 2x512mb and 2x1gb.

What I meant was that something like 1x1GB and 1x2GB would not run dual-channel.

Basically, both "channels" just have to have the same layout (say, 1GB and 1x512MB, or 2x1GB or whatever else you can think of. As long as each stick can be paired with another of the same size, you can run dual-channel)

 

That is what this is, it only has 2 slots but this is how the MoBo sees it and it works as dual channel. So in a notebook that's dual two diff size sticks do run in dual channel.

 

so does running a 2gb and a 1gb stick make a difference or not?

 

No, 3% which is not much.