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Convert Unneeded VRAM Into A Storage Device
Pawel Kot writes "Have you ever thought why does your graphics card has so much memory? Do You think you have not enough RAM or awfully slow swap file? Do you need fast ram-disk or diskless machine? Go for it! Take one of these cheap 128MB graphics cards and enjoy the speed. Michal Schulz wrote a good description on how to take the advantage of not used video card memory."
If you HAVE a new 128 mb video card (which isn't that cheap!), you probably also have a fast processor and motherboard, and lots of memory anyway.
I strongly doubt you would buy a fast processor with an agp motherboard (needed for the card), and desperately needed memory so badly, that you take from the 128 mb video card.
Would the speed of the VRAM be affected by the AGP read back bandwidth issue? I'm looking for the story that was posted on slashdot a while back, but the search function is less than adequate.
On another note, this would be usefull for older machines that only have SIMMS and use EDO/FP RAM which is a lot more expensive than todays SD/DDR RAM. But, alas, those old machine don't have AGP ports. So, really, I don't see the point to this.
Cthulhu Saves.
What if all banks or the memory addressable by the controller are filled? This is a nifty little solution. I currently have a slightly older machine that is maxed with 768 megs of PC133 memory (3 banks, max support 256 per bank).
It's currently being employed as a database and fileserver. There is a possible project coming up where the database will be quite a bit larger--768 will probably be used up--but this is not really essential. A ramdisk may be necessary. I could go out and buy a new machine, but I don't have to. I could use this fun method. This is a nifty solution for a ramdisk.
Are there any PCI cards on the market that are made just for this purpose? e.g. not a video card, but just a PCI card with DDR or DIMM banks and maybe a controller (not talking about those cpu/dimm pci machine on a card setups).
Here's some instances...
/tmp on headless servers? (Its common to leave a video card in headless servers for maintanance).
I just happen to have a nVidia geForce2go which I'm using in vesa mode becasue the nvidia module is proprietary...
Now I can swap to the video memory I'm not using and put that memory to use.
How about using that video memory for
I just don't understand why people are so negative when people have come up with a new way to show just how flexible the linux kernel can be... just because some feature doesn't meet your needs doesn't mean it doesn't meet mine.
If you want a one size fit all solution, then try some of those companies in the northwest part of the country.
This goes to show how virus authors's creativity evolves pretty fast, its funny how nowadays someone is showing how to use VRAM for legitimate purposes. Who would have known? Those crazy VXers thought of it first.
"The lesson to be learned is not to take the comments on slashdot too literally." --Vinnie Falco, BearShare
Say you want the hide "data", outside of normal memory. This a great way to add secure memory.
Write a fast bitblit routine to erase the "hidden memory. Use the graphic engine to add real time xor of crypto keys.
Don't think of it as just memory but think of it as secret memory.
Shaun
I used a similar technique on my XT compatible after I upgraded it with a VGA card with 256KB of RAM on it (long after everyone had thrown away their XTs). So long as you managed to avoid writing into the visible screen, a lot of it could be used for storage (with a bit of work on the page selection registers). I still have that machine. It's got 640k on the main board, 256k on the VGA, and 2 MB on an EMS 4.0 board. (2.875 MB total) There were times when I used every byte.
Of course there's a big difference between boosting a maxed out XT and expanding the capacity of your P4 2.8Ghz from 2GB to 2.064GB.
Support SETI@home
Yeah, right.
Think about the fact that a old of older pentium 1/socket7/super7 motherboard chipsets can't handle caching about 64 meg of ram. As a result if you add more ram the system may slow down because the L2 cache can't address about 64. Also, simms tend to be expensive. Now if you take a old pentium for a router or fileserver and you have a few old 4 meg or so video cards that X might not support anyways you can configure them as swap devices which a) you don't have to worry about slowing down the system due to L2 caching addressing limits b) swapping to ram devices is a hell of a lot faster than swap. This hack allows you to add some more life to a few older systems at the cost of a few pci slots.
I know this hack isn't great for newer systems but I have plenty of older boxes that can take advantage of this nicely.
auto262814@hushmail.com
not_cub
q='echo "q=$s$q$s;s=$b$s;b=$b$b;$q"';s=\';b=\\;echo "q=$s$q$s;s=$b$s;b=$b$b;$q"
I used this trick long long times back. I was a unix programmer but was using DOS based gateway so that I can use the novell servers in NYNEX ( you may remember who NYNEX was ). I was running short of memory by about 10 - 20K bytes and finally used this video ram for keeping my data structure. There were about 11 TSRs you needed to load to get IP and IPX stack going on DOS.
If your voice mail boxes work even today ( unless they threw away the code
Anyway, these are not the brightest momenst of my programming life but sure was interesting.
sometimes we get servers thrown in our laps that already have gfx cards which aren't needed. my last Sun came with 128mb video card plus an onboard 64mb card. i don't use either one since i use serial console on the thing.
I'm working on cd's that will install themselves into memory filesystems. Problem is, to get a decent set of apps i need a lot of memory. Using vram would be very nice, maybe not for a machine that i would spec out since i'd buy it with enough RAM, but what about borrowing/hijacking machines? Imagine using this cd to go to library, boot computer from cd, cd ejects (so there's no trace of you since upon reboot, mem is wiped), you walk on. what you left behind: a machine running gnutella and using memory file systems to store files on. getting more space from the vram would be essential.
-f
www.blackant.net
Basically Apple is finding a use for all of that VRAM while users are futzing around not playing 3D games. Granted, it's finding interesting ways to accelerate 2D video and using the AGP to pull from main RAM as well, but it's in the same sprit as stuffing random data in there.
Rather than buy an extra card for this purpose, the question to ask is how much of that 128MB am I using day-to-day. If the answer is *none* (as Apple determined) then this is a good thing.
I've often wondered why operating systems today require so much RAM in the first place. Most people just want to browse the web, check their email, and perhaps play some music. Why does Windows, or any other OS, require such resources to pull off these relatively simple tasks?
Ouch! The truth hurts!