How much ram will I be able to use?

ehanger

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OK so I want to get dual GTX 480's and an i7 930 rig but if I got all that then I wouldn't have enough money to upgrade to windows 7 (or any other 64-bit OS) so id be stuck with XP 32-bit for a while until I got the $100.

My question is how much system ram will my OS see if I have dual 480's with a combined 3gb of v-ram. I have heard that with SLI your total usable video memory doesn't double by adding a second card, but im just making sure, so maybe that would only be 1.5gb total. If my memory serves me correct a 32-bit os can use up to 2^32 bytes = ~4.2gb minus other ram/cache. So if I had 3gb of system memory that would only leave me with 1GB of usable ram???

Cause that would really suck and would make most of my games unplayable with only that much usable ram.
 
It depends on what your mobo and cpu can support is the quickest answer, Decide on your new Mobo, and read the specs as to ram support, then do the same for your intended proc,
If you use Win7 or Vista, you can utilise readyboost, slap a flashdrive in a usb port and dedicate the memory to R,boost, system will use the memory as ram
Moto
 

sgt bombulous

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Why do you need to start off with dual GTX 480's? I'd recommend just getting 2 eVGA 460's for now and then wait to see what comes out this fall, then you could step up if they release anything better than the 480 (which is bound to happen).
 


1) I don't think the video card ram is additive and deducted from what you can use in 32 bit.
2) If you are a student, see if you can get an academic license for windows-7. It should cost about $30.
3) It might be better to get just one GTX480 up front. Unless you are gaming at 2560 x 1600 you will still do very well, and may even want to pass on the second GTX480 when you have the cash. They will only become cheaper later when new stuff comes out.
 

ehanger

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I play crysis at 5040x1050 and with my old 5870 the game was pretty much unplayable at that resolution (like 20fps). So In order to get framerates averaging at least 40 I would need GTX 480 SLI.

I am a highschool junior so I don't think I would be able to get a student license unless I was in college.

 

sgt bombulous

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I see your point. I still don't think that 2 480's is a good idea. NVidia is bound to release a dual GPU card based on GF104 with all cores... Or a 512 core GF100.
 
High school junior... so minimum wage job... leads me to think you should just beg your parents for that extra $100.

Anyway, sorry if that was offensive. Why not go with a second 5870? No matter what you do, not too many games will let you max out their settings + have AA when using 3 monitors. I just read a review, and yes SLI 480s beats the pants off CF 5870s, but even then the 5870s could play at high settings without AA.

Or you could save money by getting an i5 750 or even an i7 860 on the P55 chipset. Or stick with the i7 and X58 chipset, and simply downgrade to dual channel RAM instead of triple and maybe buy that extra stick down the road. From all the reading I've done, 32 bit OS's can only use about 3.3gb of RAM. VRAM is a bit different, firstly it doesn't add up if both cards are 1.5gb VRAM, then with 2 480s you still have 1.5gb VRAM. I don't know that the OS affects GPU RAM usage much, but even if it does your system memory will definitely be limited more than the GPU.

As far as GPUs go you don't need more than 1GB. The same review about 3 monitor set ups compared 1gb and 2gb versions of he 5870 and only in maybe 1 or 2 benches did the 2gb version show any improvement, and then it was only by 1-2fps.