A question of RAM

Hi there.

If i installed 3GB of ram on a vostro using XP Home, will it all be used? Will installing 2+1GB affect performance, assuming that the vostros are dual channel.

another niggling question i've always had is how much of 4GB can be utilized by XP. I know only 3GB can be used for applications, does that mean some of it still gets used by other things? Is installing 4GB still worth it?

I really do need more than 2GB of ram. Task manager is telling me im using 2.09Gb now, and i only have 2GB installed!

 

2Gb is probably plenty, depending on what you use the computer for.

The system will still use all 4GB, its just that it will not all be available to Windows.

Windows XP (32 bit) will only usually use anywhere from 2.5 to 3.5 GB. Anything more than that pretty much does not exist as far as the OS is concerned. Here is a great article that explains it:

http://en.allexperts.com/q/PC-hardware-CPU-1023/Windows-XP-memory-limit.htm

 

The reason for this is that the way that OS's communicate with your different hardware cards is by making it so that certain addresses in memory don't actually correspond to RAM but instead correspond to things on the card. For a video card for example, the VRAM is 'mapped' into RAM, that is, each byte of VRAM is given an address in the normal 4GB max memory space. So the more VRAM your video card has, the less maximum system RAM your computer can actually use. Theoretically, if you had a 1GB VRAM video card under XP, your max memory would go to less than 3GB (minus 1GB for the video card and then all of your other cards and bios etc.).

So it's impossible to use all 4GB in a 32-bit OS*. In a 64-bit OS, the number of memory addresses that can be used is huge, so there's plenty of room for system RAM and all of the memory addresses for your cards to co-exist, at least for the foreseeable future.

*There is an exception to this rule, but only for special server motherboards/cpus, and it is obsoleted by the move to 64-bit: http://en.wikipedia.org/wiki/Physical_Address_Extension

 

I see. Will my best option then be to install 3GB? Will that present a problem with the presumably dual channel architecture? I dont actually know if notebooks are dual channel since alot of people seem to offer 3GB notebooks.

 

As far as i know the dual channel will not work unless you instal 2 memory sticks of the same specs, and some people say they really dont notice the difference in using dual channel, what is for certain in my opinion is better to have 3 gb with no dual channel than 2 gb with dual channel

 

sounds right.

 

Look you can add a 2GB stick your computer and you should see a significant improvement. You can add 4GB but it won't be used by the system. Even with the 8600M GT taping into it. Windows will only recognize roughly 3.2 GB of RAM.

PS Each GB of RAM is actually 1024 MB and 2 GB will equaly 2048. That's why it says your system is using 2.09GB.

Basically I would install a 2GB stick and wait for the drivers to be smoothed out in Vista 64bit before I upgrade to 4GB. Hope this helped.

 

yeh im planning to sell one of the 1GB stick on ebay(the easier to reach one).

Dell doesnt advertise the 8600GT they use as having hypermemory. have they disabled this? I don't think i would need it anyway. 256mb dedicated seems plenty for the 8600GT.

 

Why don't you just install the 4gb. Ram is so cheap these days what is 1 more gig