Onboard RAM & Video Cards

[Myke 0]

I figure this is a good place to get an answer for this. My boss and I were discussing how onboard RAM is affected by a video card. While we both agree that video cards have their own RAM, I've also read about how it will feed off of the onboard RAM, making the OS say that it's only utilizing 3.5 GB of the 4.0 GB that's installed. Essentially, I'd like to get a full 4 GB used by the OS, but we can't find any definitive information regarding this issue, just speculations.

 

Anyone know anything about this? I've got some ideas cooking in the back of my mind in dealing with my newly built box, but this issue is kind of putting a hang on it.

 

As always, thanks in advance.

[DosFreak 2]

32bit Windows limit is 4GB (and you really won't have 4GB more like 3.5GB or less as you noticed). Anything more than that and you need to use 64bit. (You can use the PAE switch in 32bit Windows but it's not recommended due to poor driver support).

 

 

This article sums it up nicely (and is a good site that should be in your RSS reader:

 

http://www.codinghorror.com/blog/archives/000811.html

 

 

[jmmijo 1]

Yeah, pretty much what dosfreak says, for an example I will give you my scenario:

 

I have an older Dual-Xeon motherboard based around the older Intel D875P Chipset along with the 6300 SB for I/O.

 

Now this was a good chipset in it's day but only supported the older DDR1 memory type up to 4GB total, which is what I have installed.

 

I'm using a 64-bit Xeon CPU but when I read the POST message it only shows about 3.4GB available when it shows I have 4GB installed.

 

Well with that chipset and so many others including the Intel D915/945 they were limited to a max of 4GB, but anywheres between 3.2~3.5GB could be mapped for the OS to use.

 

So even if you have a 64-bit OS like I do, it doesn't matter if the chipset is limited to how can be mapped.

 

Now for my gaming rig I use an MSI 790FX chipset by AMD along with a Phenom X4 CPU and Windows Vista Business 64-bit Edition which I dual boot with Windows 7 BETA 64-bit Edition.

 

I have 8GB of DDR2 memory installed and it can see the entire amount.

 

Many of the current motherboard chipsets from Intel, AMD and nVidia can address 8GB or 16GB.

 

The Intel X58 for the new Core i7 CPU's I think can address up to 24GB of memory which is great for users that want to do a lot of video and/or graphics work, not just gaming, that falls under a different category as games need to evolve to 64-bit platforms to really take advantage of the added memory space

[Myke 0]

Well, with that being said, I pose another question: With the provided article even stating that the video card does feed off of the onboard RAM, and the memory hole also sucking some of the potential RAM from the system, could I add (say) 5 GB of RAM to my system, whereby the memory hole and video card and use up some of the onboard RAM, which would allow the OS to use a full 4 GB?

 

I have a Phenom x4 CPU and nVidia GeForce 8500 GT (silent running) on a Biostar board with an nVidia chipset (everything is new, less than a few months old). By what you have stated, my machine should be able to deal with it, but my 32-bit OS can only handle 4 GB.

 

If the answer is no, then how much of a pain would it be to upgrade from a 32-bit to a 64-bit OS? Is it a clean install or a simple upgrade?

 

Thanks to both of you for your responses, as they've been very helpful in aiding me in my understanding of this topic.

[Philipp 6]

I haven't tried this yet, but it seems you can also use the unused memory as RAM disk: http://schichtleiter.1338.at/?p=254

 

An upgrade to a 64-bit OS will require a clean install

[jmmijo 1]

Originally Posted By: Myke

Well, with that being said, I pose another question: With the provided article even stating that the video card does feed off of the onboard RAM, and the memory hole also sucking some of the potential RAM from the system, could I add (say) 5 GB of RAM to my system, whereby the memory hole and video card and use up some of the onboard RAM, which would allow the OS to use a full 4 GB?

I have a Phenom x4 CPU and nVidia GeForce 8500 GT (silent running) on a Biostar board with an nVidia chipset (everything is new, less than a few months old). By what you have stated, my machine should be able to deal with it, but my 32-bit OS can only handle 4 GB.

If the answer is no, then how much of a pain would it be to upgrade from a 32-bit to a 64-bit OS? Is it a clean install or a simple upgrade?

Thanks to both of you for your responses, as they've been very helpful in aiding me in my understanding of this topic.

If you are referring to a Windows OS flavor, I can't say I've ever tried to upgrade from a 32-bit version to a 64-bit version.

I always setup a new HDD or partition and install the new OS there and migrate and data files I need over to the new install.

This also allows me to dual-boot if neccessary into the older 32-bit version.

[Myke 0]

Originally Posted By: Philipp

I haven't tried this yet, but it seems you can also use the unused memory as RAM disk: http://schichtleiter.1338.at/?p=254

An upgrade to a 64-bit OS will require a clean install

Thanks for the link. I'll have to tool with that a little bit.