Solved Huge lag when running on 2 videocards

[alumahai]

I do a lot of gaming on my computer, but also do a lot of work. If you've never tried it, 4 monitors really helps with AI and coding assignments. I do have a few problems gaming however. I run 2 monitors on my GTX 550, and 2 more on my GT430. When I running something on my GTX 550, I sometimes pull up firefox on the monitor directly to its right, running on the 430.
Either of these cards can run the game itself just fine, but when I do this, I often see my performance in game drop drastically, sometimes down by 30 or 40 fps.
I have been thinking the issue might be bottle-necking on the motherboards pci-e, but before I go spending money on upgrading my motherboard in HOPES of fixing this, can anyone confirm if that's the issue? Do I need to look for a 2x 16 pci-e board? could it be a processor limitation?

 

[Dude]

To run 4 monitors I would think a video card with more vram would help.

 

[AddRAM]

I would get a better card. 30 to 40 fps is not too bad during gaming.

Asking the card to run 4 monitors is a lot.

 

[Layback Bear]

Just to add a little; I would recommend replacing the power supply. LSP power supplies at best are iffy.

 

[alumahai]

I would get a better card. 30 to 40 fps is not too bad during gaming.

Asking the card to run 4 monitors is a lot.

well that's part of the issue. I can play, a bit older of a game now but to show my point, fall out new vegas on any monitor. With maxed graphics, I get 60 fps on the 2 550 monitors, and 25 fps on the 2 430 monitors. But, if I try to play it on my 550 while I have firefox open on one of my 430 monitors, I get 10-20 fps. Going the other way, I get (surprisingly) 18-25.

So the 430 is causing the problems? I guess Ill have to borrow another card and see if it still happens.

 

[Faladu]

If going for 2 cards, I believe it's best they be the same model, that 430 is low end, so yeah this slowing, doesn't surprise me at all, plus a lot of motherboards have multiple PCI Express slots for video card but they aren't necessarily all rated 16x lanes, 1 is, but the others, you might dip to even as low as 4x.

If that turns out to be the case, I would upgrade to one very strong card instead and as much VRAM as your budget allows, looks like 2gig at the very least, is needed.

 

[alumahai]

If going for 2 cards, I believe it's best they be the same model, that 430 is low end, so yeah this slowing, doesn't surprise me at all, plus a lot of motherboards have multiple PCI Express slots for video card but they aren't necessarily all rated 16x lanes, 1 is, but the others, you might dip to even as low as 4x.

If that turns out to be the case, I would upgrade to one very strong card instead and as much VRAM as your budget allows, looks like 2gig at the very least, is needed.

I figured I would upgrade my computer once my classes let out for the summer.
I intended to keep the 2 separate cards, as a powerful 4 monitor capable card would be pretty expensive, but to replace my main card with a newer 650 or 660, and to shift my current 550 into the secondary slot, where I don't need as much power, so long as it will actually fix this.
I believe the issue is from splitting of the pcie bandwidth, but wanted to ask to be sure. With some clarification, I would also like to upgrade my motherboard to allow for faster speeds with the harddrive/usb, as well as 8x/8x or even 16x/16x pcie support, since I'm pretty sure my current board doesn't.
I was also considering a new processor if I need it.

If anyone can guarantee me the problem would be fixed, or even suggest upgrades, it would be greatly appreciated.

 

[Faladu]

I would just go with a superb video card and up your power supply if it's required to do so, both of which can be moved over if you upgrade system wise later, just be sure the card has 4 monitor support, I'm thinking a Radeon HD 7870 might be the right fit for you, just off the top of my head.

Like this one, look at the back ports photo, it actually has 5! The AMD cards are known for more monitor support.

XFX Double D FX-787A-CDFC Radeon HD 7870 GHz Edition 2GB 256-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video Card - Newegg.com

For another chunk you can get what I use, a 7950: [notice the free games this one is offering with atm] [4 ports on back]

Newegg.com - SAPPHIRE 100352-3L Radeon HD 7950 3GB 384-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video Card

For 4 monitors, you need a beast of a video card . Go high or goodbye...

 

[alumahai]

Will that actually support 4 monitors though? I mean, I have a total of 6 slots on both my cards, but each only supports 2. And what exactly is the advantage to using 1 card over 2?
Ive got a friend that did the same setup as me, 4 monitors across 2 cards, except he dropped $3,000 on his parts. Specifically, he had an ASUS rampage 4, and 2 560ti's. I never noticed this happen with his.

 

[Faladu]

Yes those support 4/5 monitors, your problem is you have 2 different cards in a motherboard, and 1 is really weak and the other isn't a screamer either, when using 2 you should be using cards connected up and same model.
[SLI (Nvidia) or Crossfire (AMD)]

Even in these modes the loads get split, not a combined performance.

SO instead, I am suggesting you just get one beast card, otherwise you are likely taking a performance hit on a 2nd anyway, even if you had 2 7770s for instance, if it's not a really higher end motherboard, the 2nd+ PCIe slots are not 16x, just the first one is.

You have been given the answer: BEEF UP YOUR CARD!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

You think they put 4 ports on the card just for the fun of it?

Just read part about your friends now old rig, yeah, he has 2 of the same MODEL card, like I said.\

The other thing to do to BEEF up is getting a better CPU, other than that you are practically into buying a whole new RIG.

Other option is get a 2nd mediocre rig and do 2 monitors on each.

There is nothing else to talk about here, there is no magic to be had with that 2 card scenario of yours, it's as bad as it should be, because the hardware is not made to run different class video cards.
Got it? [$$$$$$$]

I realize that is not what you wanted to find out, but that's the harsh reality.

 

[alumahai]

Seems like I annoyed you... Sorry about that. I was just trying to figure everything out here... I had thought that the same model card was only needed for doing sli.
Also, I didn't realize most high end cards supported 4+ monitors now, as I looked a while back and there weren't really any that did. Now I see pretty much all nvidia 600 series do.

 

[Dude]

alumahai,
I don't think he was annoyed. He was pointing out the blunt truth. You can only do so much with your system and I think that's the point he tried to make. He was pointing out upgrade options, and the cost/performance benefit. A single high end card has advantages over a dual card set up.

 

[Faladu]

Yeah I am not just letting you know u are at the end of the rope!!!!!!

You are at the UPGRADE crossroad.... choose wisely!