single or dual model memory...does it mater?

[char1ie]

Hiya,

thinking of buying a Corsair 1Gb XMS2 DDR2 PC5400 (240dimm) stick...but most memory makers seem to market modules in pairs (say that pissed)...is there any benifit to buying 2 x 512 insted of 1 x 1024?

also...already have 512 samsung stick in machaine at mo..lost box and cant be arsed to take it out and have look model it is at mo...but in general..would there be any problem leaving the samsung stick in with the corsair ram? they no doubt run at different speeds, latencys etc...or is more ram..simply better?

Asus P5GD2 PREMIUM
Samsung (sumin ram?)
Radeon sapphire 800xt
P4 3.2 540S
Western dig cavier 120g hd
Thermaltake Tsunami dream case

[schmunk]

is there any benifit to buying 2 x 512 insted of 1 x 1024?

Not as much as some would have you believe (and there is certainly no benefit in paying extra for 'matched' pairs)

[Smokey21]

Not as much as some would have you believe (and there is certainly no benefit in paying extra for 'matched' pairs)

Of course there is. Why wouldn't you? it hardly cost any more. If your board has dual channel, it's stupid not to get 2 sticks. And matched pairs is more likely to overclock better, and have less compatibilty issues. Ram can sometimes be perky on certain mobo's.

[Dougal]

I have noticed that some articles from diff websites have said that Dual sided memory doesn't make a difference if you put it in a 2x config as each stick acts as dual.

Don't flame me, I have never tried it.

[herbert_goon]

I think it's simple - dual channel does equal double theoretical bandwidth, but in reality, few app really demand it.

i.e.

Single Channel PC3200 = 3.2gb/s
Dual Channel PC3200 = 6.4gb/s

*theoretically*

[StormPC]

I think it's simple - dual channel does equal double theoretical bandwidth, but in reality, few app really demand it.

i.e.

Single Channel PC3200 = 3.2gb/s
Dual Channel PC3200 = 6.4gb/s

*theoretically*

It has nothing to do with theory. It has to do with performance. Some people do not run high performance applications (probably you from your post), but for those who actually need and use a powerful system it is rediculous (and a waste of money) to not utilize dual channel.

As Smokey said, matched pairs are more likely to overclock better (like a 3500+ over a 3000+ might) but it is certainly not a sure thing. It is possible to get two individual sticks of the same memory that overclock better than a DC kit, but not as likely. If you don't overclock it makes no difference at all.

You would have to run both sticks in single channel mode. There won't be any problem if you put them in the correct slots, but in most cases you would realize more performance from simply purchasing another 512MB stick and running dual channel than purchasing a 1GB stick and running single channel.

[Nox]

I would get the 1x1024 for any system at the moment. It may be a fraction slower than a 2x512 system, but will let you put in another 1x1024 in 6 months time when the game you want to play has it as a requirement.

Nox

[TooNice]

Thats what I am thinking of doing as well, for my next PC.

On a side note, how do I read the amount of physical memory currently used under XP?

Do I only look at the "Physical Memory" box and substract the total with the available? Or do I look at the "Commit Charge"? (which also include Virtual Memory if I understand right). Either way, it looks like a lot of memory is being used for not very much stuff. I only have ~200MB Physical memory available (594MB Commit Charge). Either way, its kinda a lot considering that I am not even running games right now...

[Smokey21]

I would get the 1x1024 for any system at the moment. It may be a fraction slower than a 2x512 system, but will let you put in another 1x1024 in 6 months time when the game you want to play has it as a requirement.

Nox

To me, thats completey barmey. You could say about upgrading in 6 months, about anything to do with PC's, why wait 6 months to take advantage of what your mobo has right now?

You can always sell the 2x512mb if you wanted. New A64's work fine with 4 Dimms anyways.

[herbert_goon]

It has nothing to do with theory. It has to do with performance. Some people do not run high performance applications (probably you from your post), but for those who actually need and use a powerful system it is rediculous (and a waste of money) to not utilize dual channel.

You can tell what apps I run from my post? That is rediculous

IMHO 1gb single channel is faster that 512mb dual channel in a windows app, especially with the VM techniques in use. Each VM will aquire a slice of virtual ram and the moment you breach the physical limit you will hit virtual memory and you whatever point whatever petabytes per second memory will drop down to good old 133 or 150 mb/s. Why do you think benchmarkers have to close as many other apps an services, set affinity etc etc, yes been there and done that and it's a joke. Being able to tweak hardware is one thing, but if you don't understand the software, you will end up with a hot rod with wooden tyres...

And as far as thoery goes, 6.4gb/s is a theoretical maximum, or of it is clearer, "peak performance", to say otherwise is simply untrue. If you have a 200watt amplifier, that means it will drive speakers with 200w power when you turn it up, not all the time