580 SLI + gt730 VRAM issue

[sydjy]

Hello everyone !

First of all, excuse me for my english, it's not my native language

I have a very tricky probleme that you guys gonna enjoy think on :


My actual configuration :

cpu : i7 920
mobo : p6t se (old 1366 socket)
GPUs : SLI gtx580
RAM : crucial 3*4g (trial channel)
SSD : corsair 120go
on Windows 7 x64

I currently have 2 display, my main ACER 1080@120hz, and a spare normal 1680*1050 display.


I wanted to add a 3rd monitor (not for surround or gaming, juste a normal display for video/browser).

I know that with the 580 series, i can't run more than 2 display with SLI enabled (i don't want surround), so i brough a GT 730 just for the the accessory display.

THE PROBLEM:

I don't know why, but the OS copy in the gt730 the same data in VRAM than my 580, even if there is nothing connected to that gt730 !

For exemple : i use to run a TERA (an online game), with only the 580's on the PC, like i always did, everything is fine (With or without SLI enabled)

But if i just connect the GT730 to the motherboard (with no monitor connected to it, no 3rd display connected or whatever else), it copy all the game data on the gt730 VRAM too, and of course that cause the game to run like shit due to the low speed/capacity of vram.


Why the OS send that to the gt730 too ? I tried enabling/disabling SLI on the 580, tried various combo of video output on the 580's, but it's always the same.

Screens in idle on windows7



As you can see, there is data on the 730's VRAM without even a display connected to it ! (Like i said, it happen with game data too)


How do I make this gt730 to run by itself without slowing down my 580sli ?

I hope someone has the answer to this because i'm driving nuts


Thank you very much !

 

[digitaldurandal]

Hello everyone !

First of all, excuse me for my english, it's not my native language

I have a very tricky probleme that you guys gonna enjoy think on :


My actual configuration :

cpu : i7 920
mobo : p6t se (old 1366 socket)
GPUs : SLI gtx580
RAM : crucial 3*4g (trial channel)
SSD : corsair 120go
on Windows 7 x64

I currently have 2 display, my main ACER 1080@120hz, and a spare normal 1680*1050 display.


I wanted to add a 3rd monitor (not for surround or gaming, juste a normal display for video/browser).

I know that with the 580 series, i can't run more than 2 display with SLI enabled (i don't want surround), so i brough a GT 730 just for the the accessory display.

THE PROBLEM:

I don't know why, but the OS copy in the gt730 the same data in VRAM than my 580, even if there is nothing connected to that gt730 !

For exemple : i use to run a TERA (an online game), with only the 580's on the PC, like i always did, everything is fine (With or without SLI enabled)

But if i just connect the GT730 to the motherboard (with no monitor connected to it, no 3rd display connected or whatever else), it copy all the game data on the gt730 VRAM too, and of course that cause the game to run like shit due to the low speed/capacity of vram.


Why the OS send that to the gt730 too ? I tried enabling/disabling SLI on the 580, tried various combo of video output on the 580's, but it's always the same.

Screens in idle on windows7



As you can see, there is data on the 730's VRAM without even a display connected to it ! (Like i said, it happen with game data too)


How do I make this gt730 to run by itself without slowing down my 580sli ?

I hope someone has the answer to this because i'm driving nuts


Thank you very much !

I don't know the answer to your question but I do have a question.

Do you need the third monitor even while gaming?

If not then the best solution might be to hook monitor 3 to 580 #2.

When you are not playing games disable SLI and enjoy the third monitor.

I am trying to remember when I had 570 SLI if I had this problem but I cannot recall. I think I left Surround on but when playing some games if set to 1200p it would just make 3 images and id turn two screens off? Sorry it has been too long.

Another possible solution would be to sell all three of those cards and buy something newer with that cash. It looks as if the 580 is selling in the US for about $100 used still

So if you can get $200 you could almost get r9 290 with that. It will run 3 monitors by itself and especially if you are not doing triple monitor gaming it should be fine performance wise.

 

[sydjy]

Thanks for your answer !

The things is that i actually use that 2 spare monitor while gaming (monitoring / web / social..), the whole process of this is to make that display working while i play

Surround is not an option, one of the monitor is 1680*1050, so it gonna make the surround looks very blurry, and in top of that i use the main monitor in 120hz, something i can't keep with surround.

I actually can't replace the GPU, they are in a WC loop with the CPU, they work very well, without the gt730 of course..)

I really want to know what's the problem here, in the paper, everything should run fine..

 

[Deders]

That 135MB of data is likely to be just the memory it needs to run the desktop and Aero. How is the 3rd monitor set? I presume it's not set to mirror?

Edit: I'm also wondering why the 730 is the 1st gpu. which PCIe slot is it in?

 

[sydjy]

The 730 is on the last PCIe of the mobo.

As you can see, when i take this screenshot there where no screen connected to the 730, so no reason to have any memory loaded. For the 135MB it was just an example to show that the loaded vram amount is the same than the 580's. If i load a game, the 730 gonna load ass much as the 580 too.

There is no 3rd monitor, i didn't even tried to put it since it's already a total mess for the moment, the 730 is just pluged into the mobo, nothing else.

 

[Deders]

Have you uninstalled and re-installed the driver?

 

[digitaldurandal]

I actually can't replace the GPU, they are in a WC loop with the CPU, they work very well, without the gt730 of course..)

I still would remove them from the loop and sell them and get a 290. It will do what you are wanting to do with a single card. I think you are going to have serious headaches with SLI + 1. I know it isn't really a great answer to your question but I think it is the best move.

The fact that the 580s still have pretty fair value for a card 3 generations old and that the 290s are so cheap at the same time means this is a great opportunity to trade up. I think it will be a while once the 290s are gone before you see something with that level of performance for $250 brand new.

If you find the solution be sure to post it in case someone else tries the same thing as you and gets stuck.

 

[sydjy]

@Deders : Yes I did this multiple time, with differents drivers version to be sure it's not a specific driver issue.

@digitaldurandal : I'm gonna do an brand new build when skylake rise up, for that I don't realy want to invest in my actual build know, the performance I get are enought for what i need. But you're right about the 290, that would have been such a great boost.

I tested to replace the 730 by a HD6450, and it work perfectly like i wanted to do with the 730, SLI work 100%, 3 display enabled.
But i still don't get why it can't work with the 730.