Memory Query re Vista 32bit OS

[neiltaffy]

Hi davey,
First of apologies as this is a simple question, but Ive read so many conflicting posts on the matter. And am completely new to upgrading


Im having trouble replying via the online helpldesk, so thought Id bring it to this forum.
As the thread ttile suggests Im considering upgrading my existing 2GB Ram to whatever the max VISTA 32 bit will allow (im trying my hand at a bit of 3d work)

I have been told via the nice person on the helpdesk the following;


"The motherboard in your PC, the Asus P5N32-SLI Premium, can support a maximum of 8GB (4x 2GB modules) of unbuffered non-ECC DDR2 800MHz RAM. It was originally fitted with 2GB (2x 1GB modules) of DDR2 533MHz RAM. I would recommend to maintain the same speed of RAM when upgrading, so I would suggest either to get more DDR2 533MHz RAM, or upgrade all the RAM to 667MHz or 800Mz RAM.

Your PC can support both 32-bit and 64-bit versions of Windows, but I would recommend to keep a 32-bit Windows unless there is some specific application you use that needs a 64-bit operating system. This is because many applications are not compatable with 64-bit Windows and it can be difficult to find 64-bit drivers for some devices (in some cases, there simply aren't any)."


In addtion to the above therefore, assuming I go for 800mhz DDR2 Ram, how much of this can I actually put in and use. I.e. is it worth buying 4gb, 3gb or what?

(Im assuming 4 is the max, but even then Im unsure if they are 4x1 GB or 2x2gb etc...)

[Splash]

It's not a limitation of Vista, it's a limitation of 32 bit OSes - they can address a maximum of 4Gb RAM. This however includes all system memory including the page file, so traditionally this means you will see a maximum of 3.5Gb (usually 3Gb) whilst using a 32 bit OS. The ONLY way past this is to use a 64 bit OS, as they can address a far larger memory range.

Seriously - can we get something like this stickied?

[Davey W]

Hi neiltaffy,

As Splash says, the 32bit OS causes the limitation so if you absolutely positively *had* to have more than about 3-3.5gb you'd be looking at a 64bit OS.


Splash,

I understand the request but if I sticky one commonly asked question I'd end up having to sticky a whole load of them and before you know it, the first page is stickies alone. I'll have think about possible solutions (maybe a lengthy FAQ).

Davey

[neiltaffy]

thanks both,

I realise its a limitation of any 32 bit, rather than 64 bit OS (not just Vista)
as I said Ive seen other posts on related matters, it was just a simple q. of what mem my mobo would be able to cope with, ( i.e. the one Im looking at is 2x2GB DDR2 ram @800Mhz).

Looking at both yours and the Helpdesks answer earlier though, it seems this should be fine.


Just I read a few scare stories elsewhere , and Ive never even fitted memory before! Wanted to ensure I was doing the right thing before going ahead and buying.

[neiltaffy]

this being the case does anyone recommend any particular links to 4GB memory upgrades that will work for my motherboard ?


ta

[DrATty]

The 4Gb limit imposed by 32-bit OSes is due to that being the amount of memory the OS can address ie. 2power32~4Gb. The 4Gb includes graphics memory and that used by the motherboard so you will often see less eg.~3.2Gb with a 768Mb graphics card.
A 64-bit OS can address more memory; 2power64~18billion Gb!
There's a lot written about the pros and cons of 64-bit. I've put together a summary of my understanding of this.

Drivers
The availability of 64-bit drivers is improving but it's likely that you'll have something for which there are none.

32-bit Compatibility
Although the OS itself is 64-bit most software isn't. Most 32-bit software will run under Vista 64-bit but some won’t. 32-bit anti-virus software won't. Also, there are still a few 16-bit programs around and they won't run on a 64-bit OS while they will on a 32-bit OS. Quite a few 32-bit programs use 16-bit installers and can't be installed on 64-bit OSes. 32-bit shell extensions aren't supported.

Memory & Execution Speed
Most 32-bit software will run under 64-bit Windows but each application will only be able to use 4Gb of memory at most (usually just 3Gb and often less as it's unlikely that it was written with 64-bit in mind.) This is more than with the 32-bit OS, but with a 64-bit OS, the OS itself uses more memory. 64-bit code is 'longer', and, because 32-bit applications can only use 32-bit library files, both 32-bit application .dlls and 64-bit OS .dlls are often loaded side-by-side. The result of this is that more of the available memory is used. The 'longer' code takes more time to execute and the running of a 32-bit program is usually slower.

Unless you're planning to use applications that require, or will benefit from 64-bit, stick with 32-bit. It's annoying that some memory cannot be used but 3Gb is still better than 2. In my opinion it’s better to fit 4Gb even though only 3 or so is ‘seen.’ The benefits of dual channel memory will be lost when fitting just 3Gb. It’s the price you pay for performance.

[neiltaffy]

Many thanks DrATty, v. useful!

I still am unsure (as there is a plethora of types on teh market) which type of 2x2 GB 800 mhz RAM to get (or better yet, a specific product that someone can recommend).

Again, if anyone has any answers I'd be v. grateful

[Splash]

Splash,

I understand the request but if I sticky one commonly asked question I'd end up having to sticky a whole load of them and before you know it, the first page is stickies alone. I'll have think about possible solutions (maybe a lengthy FAQ).

Davey

Sorry Davey - this wasn't directed at you. I'm going to create a thread in the Help - Technical and Advisory section with this info and suggest it get's stickied there. I must have seen hundreds of people asking the same (or very similar) questions since the launch of Vista, so a sticky might help.

EDIT - neiltaffy - I'd suggest you look at 1Gb modules at the moment, 2Gb modules are not particularly cost effective. I'm not particularly aware of any issues with your board, but the Corsair PC2-6400 2Gb XMS2 kits are pretty reasonable.

[neiltaffy]

Many thanks Splash,

As I said Im a total noob at this thing. The only reservation I had about choosng anything other than 2x2gb was from reading some threads in the tech help section of this forum which seemed to indicate that there may have been probs if all 4 slots on the mobo were taken up.

In addition if I go for the 800Mhz RAM, Ill have to replace my existing lot (533Mz) wholesale anyway.

[pineman]

I agree with Dr ATty.

I have fitted 4 x 1GB sticks of RAM and Vista recognises 3GB. I tried 3 x 1GB but dual channel was disabled. I also tried 4 x 1GB and enabled PAE. This appeared to work less efficiently than with 4 x 1GB fitted with Vista only recognising 3GB.

All of my slots are filled and I have no problems.

There is a view that Vista SP1 may resolve the 4GB limit - who knows?

[dangel]

There is a view that Vista SP1 may resolve the 4GB limit - who knows?

No, it won't. Ever. 64Bit Vista is there to solve the problem for you, without the need for hacks or bastardised extentions.

[DrATty]

I tend to agree that 4x1Gb is more cost effective than 2x2Gb but it does mean you have to discard some memory if you ever want more than 4Gb. It's best to upgrade in matched pairs to keep dual-channel functionality.
If you keep your 533MHz RAM, any 'faster' RAM you add will be limited to this speed.
As you mention, some owners have had trouble getting 4 sticks to work. Sometimes, adding the second bank of memory stops dual channel working. I'm not sure that these problems indicate a fault in the motherboards; more that they become increasingly fussy with respect to the memory used. It doesn't take long to find someone who found a fix by swapping their memory for new sticks of the same type or from a different manufacturer. Google is the best way to search for potential problems with your particular board.
If you have the cash, go for 2x2Gb. You could even go to 8Gb later.
Otherwise, add 2x1Gb to start with. Go with 800MHz but be aware that it will run at 533MHz with the memory you already have. Buy from somewhere that allows returns if it doesn't work.
There's a nice memory tool at Crucial. It will suggest a range of compatible memory to put on your shopping list. MESH have a smaller choice but will almost certainly have tested the memory in their PCs and it's good quality RAM.
Just make sure you can change it if it doesn't work.

[neiltaffy]

thanks all for your answers.

The Crucial tool looks useful, Ill have to wait to try it out when I get home. In the meantime, Ive noticed that
http://www.memory-configurator.co.uk...2Gb/index.html appear to cost the same asseveral of the 4x1GB ram mentioned


Ill have a look around anyway

Thanks again

[DrATty]

Nice price.
I haven't tried 2Gb sticks in my MB. They used to be much more expensive which is why most PCs have 4x1Gb.
It might be the way to go and might avoid some of the trouble seen on the Web. I tried 2 extra 1Gb sticks in my P5N32-e SLI board recently and had problems. I'm going to try a different pair but might try 2x2Gb if that doesn't work. I don't think it's a motherboard fault as such. I think they're just more particular when it comes to using all four slots. I don't know for sure but 4 sticks work for some users and not others.
I suppose there's nothing to stop you having 6Gb later either, though there's no point just now.

[ukengineer]

dual channel memory requires a matched pair (2) sticks of ram.

It was designed for 2 sticks of ram, so dual channel with 4 sticks is still not perfect, and tests prove best performance and usage is obtained from 2gb of ram, (2x1gb sticks) in dual channel.

I have yet to find a pc of same spec running better or faster than this configuration.

I have 2gb ram, my pagefile is on a seperate hdd on a seperate controller, and the pagefile is also a fixed size. Having a pagefile managed by windows, or with min and max sizes different causes a lot of disk activity and also lots of wasted time waiting for it to resize the pagefile all the time.