Widescreen Gaming Forum

I have been surround gaming for a while now, originally using a Matrox Parhelia card driving three 1280x1024 monitors, to a 8800GTX with Matrox TH2G analog, to GTX295SC with Matrox TH2G digital, to GTX570SC still with the TH2Gd. I just added a second GTX570SC, this is my first experience with SLI.

Here's my setup right now:
EVGA X58 SLI (132-BL-E758-A1)
I7-920 OC at 3.2
12G ram
EVGA GTX570SC (012-P3-1572-AR) x2 SLI
Matrox TH2G digital
1680x1050 LCD x4 - three on the TH2G, one on the other port on the same 570. I have my monitors set up in an upside down T.

After all of that, here's my questions.

1. I know that Nvidia now supports using the monitors in surround - connecting three of them to three of the four HDMI ports on the combined cards, and then driving those with SLI. Can I connect the fourth monitor but still use SLI on three of them, and have the fourth be separate within Windows? If this is possible, is the performance and/or quality going to be any better by driving the monitors directly off the 570s vs going through the TH2G?

2. If it's not possible to do that, I could add another card to my system to drive that fourth monitor separately - I have a 9800GT that would work for this and the motherboard has three PCI slots I can work with. However, the motherboard slot speeds are affected by how many cards are in the system - if there's one or two cards, the first two slots are 16x. If I add a third card, the slots are 16x,8x,8x - and my SLI setup would be across slots 1 and 2. Would slowing the slots down have an impact on things, and again, better to get rid of the TH2G with a 16/8/8 slot speed or leave things as they are?

Thanks in advance, I hope my explanations are clear enough.