Rules of RAM 4

[KMartin2004]

Hey everyone, can someone please tell me if there is a problem with mixing RAM size? For example: 256+256+128+64

if i had four slots and i out these in those slots would this be ok>

I have the A7N8X Deluxe MOBO w/dual channel 400DDR 3200
it has three slots. I have 256+256 dual channel in use. Can i buy a 1 gig chip with no prob?

Thanks,

KMartin2004

 

[bcastner]

The rules are whatever the motherboard designed decided them to be.

It is not an XP issue, it is a motherboard design issue. For example, on this page there is a thread from someone wanting to add more RAM. His motherboard supports up to 1gb DDR modules in either slot 1 or 2, but only SDRAM in slots 3 & 4, and you cannot mix DDR and SRAM.

The information you need is in the motherboard manual, or on the motherboard manufacturer's web site.

 

[cdogg]

I noticed that you are trying to run DDR in dual-channel. In order for that to occur as designed, you need two matching sticks (identical size and preferably identical type/brand). The dual-channel slots are marked on the motherboard, usually in a blue.

The max amount each slot can take is defined by the motherboard specifications as bcastner said. Most newer boards like the one you have usually support 1GB modules.


~cdogg
[tab]"All paid jobs absorb and degrade the mind";
[tab][tab]- Aristotle
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[bcastner]

The best answer you can receive would be from forum602 for any specific motherboard/RAM question.

And the issue is motherboard specific, as cdogg noted above.

 

[bcastner]

I will just add as a personal note about RAM. Given current pricing and densities, for a RAM upgrade I just throw out any module less than 256k. Buy clean new stuff, with warranty, and start from there.

I suspect within a year I will throw out any RAM module less than 512k.

If your intention is to add RAM as the OS changes, then preserve your slots. Sell your working 256 or under at E-Bay or similar if you intend a RAM upgrade. But check first as noted above that your motherboard can support such high density RAM modules.

For XP Professional, 512 is a reasonable amount of RAM. For special uses, such as re-encoding video, bump it to 2 gb. After that, unless you are very clever, it is a waste of time and money.

When the "next great OS" comes out, sell your entire box on E-Bay, and buy something brand new that matches the requirements.

 

[tf1]

No you cannot with this motherboard. If you open up your PC, you will see that it only has three slots supporting a maximum of 3 x 1GB modules.

The mobo supports dual channel memory mode (800MHz bus) but only if you install an identical pair of RAM chips in the dual channel slots.

So stick to the 2 x 256MB in dual channel mode for best performance with the modules that you own.

If you want more memory, then you need 2 x 512MB or 2 x 1GB modules as your next upgrade. However, a single 1GB module will increase your memory to 1.5GB but will run in single channel mode (400MHz): I am guessing that this will provide better performance for memory hungry applications that 512MB in dual channel mode.

Regards: tf1

 

[bcastner]

Thanks tf1,

I overstated my case. But my original thoughts are valid: this is very motherboard specific, and not an OS rule.

And I do make complememtary memory changes when tossing 64k modules.

But see the manual, or see the motherboard manufacturer web site.

 

[KMartin2004]

Thank you cdogg, Bcastner, and tf1 for all your info.

tf1, you make it sound like it would be a bad thing to go from 512 dual channel to 1.5 single. I see that it will cut the bus in half but what does that really do to someone who like to listen to music and play a few game?

More RAM with single channel or less RAM in dual channel..

With me being the average Joe at this kind of thing, what does this really mean to me?

Thanks,

KMartin2004.

 

[tf1]

It isn't a 'BAD' thing to do and that is a very good question and difficult to answer. Probably, if you really are only a light user (listen to music and play a few games), then I don't believe that you will benefit from more than the 2 x 256MB memory in dual channel mode.

Untill a few months ago, I was more than satisfied with exactly that memory configuration. Then one day I got the retail version of Adobe Photoshop Album 2 and found it took ages to catalogue all the photos I had on disk and it took even longer to make an EXE photo album to send to friends on CDR. Doubling the memory to 2 x 512MB ceased all the disk thrashing and I can now make the export album in less than 30 seconds against 20 minutes with less memory.

Unless you are seeing evidence of system 'bottlenecking' because of insufficient memory, then don't bother to upgrade, especially if you are installing a single 1GB and going single channel. Dual channel mode is worth approximately 10 - 12% performance boost when compared to single channel mode with the same quantity of memory.

Prior to getting Album 2, I found that even editing big digital photos taken on a 6MB camera using PhotoShop 7 was using nowhere near all the 512MB memory installed. Had I installed a 1GB memory module (and lost the dual channel operation), I would have noticed this loss in performance.

Use the Windows Task Manager to see if you really do need more than the 2 x 256MB memory.



Regards: tf1

 

[KMartin2004]

Thank you so much tf1. I thank you all for you time and info.

KMartin2004.

 

[bcastner]

This article takes some of the guesswork out of virtual memory under XP:

http://www.petri.co.il/pagefile_optimization.htmers.htm

 

[Freestone]

It appears as if Tek-Tips is still be having problems with posted links. Bill's link should be:

http://www.petri.co.il/pagefile_optimization.htm

 

[bcastner]

That one was likely my fault.
Thanks Freestone. It is a great article about how to objectively decide on virtual memory sizing.

Best,
Bill

 

[paparazi]

tf1
I beg to differ about your dual channel comments!
When Nforce2 came out and we were seeing all the reviews from Toms and anandtech, I remember this exact same question being answered, they tested different memory configurations from dual to single and carryied out benchmarks.
I remember the differance was between 1 & 3% faster in dual channel, basically very minimal! not the 10/12% you are reporting.
Other platforms have indeed seen better performance gains in dual channel (the new socket 939 Athlon64's for instance because it has an on chip dual memory controller) but not the Nforce2.

quote!
"what does that really do to someone who like to listen to music and play a few game? With me being the average Joe at this kind of thing, what does this really mean to me?"

"Average Joe" will not benefit in the slightest from changing from 2 x 256mb dual channel to 1.5GB single.
The applications that you are using simply will not use what you have at present.
Martin






We like members to GIVE and not just TAKE.
Participate and help others.

 

[tf1]

My understanding is that the later versions of the chipset with the later bios (as used in the delux version of this mobo) improved the architecture to gain full benefit of the dual-channel memory.

But I agree completely with your summary statement. If the current use does not demand more memory, fitting more memory will not improve performance in the slightest. In fact, the loss of dual channel and larger memory address array may in fact slow down the memory performance.

Regards: tf1