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#1
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How come RAM is taken away for video cards? Because of my videocard's VRAM?
Like I have 3 GB of RAM, but Windows show 2.5 GB. I was told because it
is a shared memory? Thank you in advance. -- "He was a musical ant. He was there for the song." --Rick (Rick Moranis episode from The Muppets) Note: A fixed width font (Courier, Monospace, etc.) is required to see this signature correctly. /\___/\ Ant(Dude) @ http://antfarm.ma.cx (Personal Web Site) / /\ /\ \ Ant's Quality Foraged Links: http://aqfl.net | |o o| | \ _ / If crediting, then use Ant nickname and AQFL URL/link. ( ) Chop ANT from its address if e-mailing privately. Ant is currently not listening to any songs on this computer. |
#2
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How come RAM is taken away for video cards? Because of my videocard's VRAM?
Ant wrote:
Like I have 3 GB of RAM, but Windows show 2.5 GB. I was told because it is a shared memory? Thank you in advance. You need an article on the "32-bit Windows memory license", which isn't really a memory license as such, but is implemented as an address space limitation. You have 4GB of addresses, some addresses are reserved for bus address decodes, leaving the rest. The video card memory needs to be decoded on those busses as well. The bigger the onboard video card memory, the more addresses needed. The remaining addresses, are used to access your motherboard memory DIMMs. If there aren't enough addresses left to access all of the memory on your DIMMs, then you don't get to use it on 32-bit Windows. Some portion of your motherboard DIMMs is then simply inaccessible. There's no address available to get to that chunk of memory. Windows then claims "2.5GB free". WinXP actually has PAE enabled in SP3. And 32-bit Windows really does have access to memory above 4GB. I know this, because on the computer I'm typing this on, my DataRAM RAMDisk software is using the top 4GB of my 8GB of RAM, as a RAMDisk, while the bottom RAM, Windows claims "3.1GB free" or so. And this works, because the "Windows memory license" only applies to Ring 3 (applications) and not Ring 0 (kernel and drivers). My RAMDisk is driver-level based, drivers run in Ring 0, and since PAE is turned on, the upper memory is actually available. But can only be used for a RAMDisk. Now, if I put the Windpws pagefile on the RAMDisk, I can "outfox" Microsoft a tiny bit. But just a tiny bit. I can run multiple programs, and actually sharing 5GB of RAM over three programs if I want. (Swapping happens at RAMDisk speeds.) But one program alone cannot have 5GB. I ran my system that way for a few days, before taking that setup apart. There were a few "glitches" that don't make the method practical. I tested it, until the glitches in the scheme showed up. If you were using 64 bit Windows, you would discover next to no penalty at all. Exceptions might include, slightly less than optimal results on 8GB chipsets with 8GB of DIMMs installed. Many other chipsets, they made the address space large enough that it no longer clips off the top of memory. For most users, when they boot into 64 bit, they no longer seem to care about those sorts of details :-) Chipsets (or IMCs) that support more than 4GB of memory properly, use "memory hoisting" to lift some structurally inaccessible memory, to above the 4GB mark. And that's part of the reason you get to use all of it, with the 64 bit OS. There was at least one (stupid) Intel chipset, where there was no hoisting, you could install 8GB of DIMMs, and the chipset prevented usage of any more than 4GB of that. Lucky you, if you bought one of those. Only one specific Intel chipset was affected. ******* A thorough treatment of graphics memory or address usage would include a description of... 1) AGP GART (and that old setting in the BIOS) 2) Shared memory for Northbridge or CPU graphics a) Static allocation for frame buffer b) Dynamic allocation only while playing 3D games c) Earlier designs that supported only static, and the user had to decide how much to donate to the GPU shared memory setting. 3) NVidia TurboCache on some $50 video cards. With some cards having only TurboCache, some cards having onboard as well as TurboCache, and so on. What a mess. But I'm not going to write those up. Because based on your premise in the question, they don't apply to you. Paul |
#3
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How come RAM is taken away for video cards? Because of my videocard's VRAM?
Ant wrote:
Like I have 3 GB of RAM, but Windows show 2.5 GB. I was told because it is a shared memory? Thank you in advance. You need an article on the "32-bit Windows memory license", which isn't really a memory license as such, but is implemented as an address space limitation. You have 4GB of addresses, some addresses are reserved for bus address decodes, leaving the rest. The video card memory needs to be decoded on those busses as well. The bigger the onboard video card memory, the more addresses needed. The remaining addresses, are used to access your motherboard memory DIMMs. If there aren't enough addresses left to access all of the memory on your DIMMs, then you don't get to use it on 32-bit Windows. Some portion of your motherboard DIMMs is then simply inaccessible. There's no address available to get to that chunk of memory. Windows then claims "2.5GB free". WinXP actually has PAE enabled in SP3. And 32-bit Windows really does have access to memory above 4GB. I know this, because on the computer I'm typing this on, my DataRAM RAMDisk software is using the top 4GB of my 8GB of RAM, as a RAMDisk, while the bottom RAM, Windows claims "3.1GB free" or so. And this works, because the "Windows memory license" only applies to Ring 3 (applications) and not Ring 0 (kernel and drivers). My RAMDisk is driver-level based, drivers run in Ring 0, and since PAE is turned on, the upper memory is actually available. But can only be used for a RAMDisk. Now, if I put the Windpws pagefile on the RAMDisk, I can "outfox" Microsoft a tiny bit. But just a tiny bit. I can run multiple programs, and actually sharing 5GB of RAM over three programs if I want. (Swapping happens at RAMDisk speeds.) But one program alone cannot have 5GB. I ran my system that way for a few days, before taking that setup apart. There were a few "glitches" that don't make the method practical. I tested it, until the glitches in the scheme showed up. If you were using 64 bit Windows, you would discover next to no penalty at all. Exceptions might include, slightly less than optimal results on 8GB chipsets with 8GB of DIMMs installed. Many other chipsets, they made the address space large enough that it no longer clips off the top of memory. For most users, when they boot into 64 bit, they no longer seem to care about those sorts of details :-) Chipsets (or IMCs) that support more than 4GB of memory properly, use "memory hoisting" to lift some structurally inaccessible memory, to above the 4GB mark. And that's part of the reason you get to use all of it, with the 64 bit OS. There was at least one (stupid) Intel chipset, where there was no hoisting, you could install 8GB of DIMMs, and the chipset prevented usage of any more than 4GB of that. Lucky you, if you bought one of those. Only one specific Intel chipset was affected. ******* A thorough treatment of graphics memory or address usage would include a description of... 1) AGP GART (and that old setting in the BIOS) 2) Shared memory for Northbridge or CPU graphics a) Static allocation for frame buffer b) Dynamic allocation only while playing 3D games c) Earlier designs that supported only static, and the user had to decide how much to donate to the GPU shared memory setting. 3) NVidia TurboCache on some $50 video cards. With some cards having only TurboCache, some cards having onboard as well as TurboCache, and so on. What a mess. But I'm not going to write those up. Because based on your premise in the question, they don't apply to you. Paul |
#4
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How come RAM is taken away for video cards? Because of my videocard's VRAM?
On 01/17/2016 03:31 AM, Ant wrote:
Like I have 3 GB of RAM, but Windows show 2.5 GB. I was told because it is a shared memory? Thank you in advance. If your machine has on-board video, there is a BIOS option as to how much RAM you want to assign to it. If you have added a video card of your own, there is no need to assign RAM to the ob-board card so you can go into the BIOS settings and adjust assigned RAM down to zero. |
#5
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How come RAM is taken away for video cards? Because of my videocard's VRAM?
On 01/17/2016 03:31 AM, Ant wrote:
Like I have 3 GB of RAM, but Windows show 2.5 GB. I was told because it is a shared memory? Thank you in advance. If your machine has on-board video, there is a BIOS option as to how much RAM you want to assign to it. If you have added a video card of your own, there is no need to assign RAM to the ob-board card so you can go into the BIOS settings and adjust assigned RAM down to zero. |
#6
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How come RAM is taken away for video cards? Because of my video card's VRAM?
Interesting. I am using PAE and have no onboard video. Oh well, thanks
anways. You need an article on the "32-bit Windows memory license", which isn't really a memory license as such, but is implemented as an address space limitation. You have 4GB of addresses, some addresses are reserved for bus address decodes, leaving the rest. The video card memory needs to be decoded on those busses as well. The bigger the onboard video card memory, the more addresses needed. The remaining addresses, are used to access your motherboard memory DIMMs. If there aren't enough addresses left to access all of the memory on your DIMMs, then you don't get to use it on 32-bit Windows. Some portion of your motherboard DIMMs is then simply inaccessible. There's no address available to get to that chunk of memory. Windows then claims "2.5GB free". WinXP actually has PAE enabled in SP3. And 32-bit Windows really does have access to memory above 4GB. I know this, because on the computer I'm typing this on, my DataRAM RAMDisk software is using the top 4GB of my 8GB of RAM, as a RAMDisk, while the bottom RAM, Windows claims "3.1GB free" or so. And this works, because the "Windows memory license" only applies to Ring 3 (applications) and not Ring 0 (kernel and drivers). My RAMDisk is driver-level based, drivers run in Ring 0, and since PAE is turned on, the upper memory is actually available. But can only be used for a RAMDisk. Now, if I put the Windpws pagefile on the RAMDisk, I can "outfox" Microsoft a tiny bit. But just a tiny bit. I can run multiple programs, and actually sharing 5GB of RAM over three programs if I want. (Swapping happens at RAMDisk speeds.) But one program alone cannot have 5GB. I ran my system that way for a few days, before taking that setup apart. There were a few "glitches" that don't make the method practical. I tested it, until the glitches in the scheme showed up. If you were using 64 bit Windows, you would discover next to no penalty at all. Exceptions might include, slightly less than optimal results on 8GB chipsets with 8GB of DIMMs installed. Many other chipsets, they made the address space large enough that it no longer clips off the top of memory. For most users, when they boot into 64 bit, they no longer seem to care about those sorts of details :-) Chipsets (or IMCs) that support more than 4GB of memory properly, use "memory hoisting" to lift some structurally inaccessible memory, to above the 4GB mark. And that's part of the reason you get to use all of it, with the 64 bit OS. There was at least one (stupid) Intel chipset, where there was no hoisting, you could install 8GB of DIMMs, and the chipset prevented usage of any more than 4GB of that. Lucky you, if you bought one of those. Only one specific Intel chipset was affected. ******* A thorough treatment of graphics memory or address usage would include a description of... 1) AGP GART (and that old setting in the BIOS) 2) Shared memory for Northbridge or CPU graphics a) Static allocation for frame buffer b) Dynamic allocation only while playing 3D games c) Earlier designs that supported only static, and the user had to decide how much to donate to the GPU shared memory setting. 3) NVidia TurboCache on some $50 video cards. With some cards having only TurboCache, some cards having onboard as well as TurboCache, and so on. What a mess. But I'm not going to write those up. Because based on your premise in the question, they don't apply to you. Paul -- Quote of the Week: "Applied mathematics will always need pure mathematics, just as anteaters will always need ants." --Paul Halmos Note: A fixed width font (Courier, Monospace, etc.) is required to see this signature correctly. /\___/\ Ant(Dude) @ http://antfarm.home.dhs.org (Personal Web Site) / /\ /\ \ Ant's Quality Foraged Links: http://aqfl.net | |o o| | \ _ / Please nuke ANT if replying by e-mail privately. If credit- ( ) ing, then please kindly use Ant nickname and AQFL URL/link. |
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