HI, Does anyone know if I should run FSX in SLI mode? I have two 9800GTX cards in SLI mode. Thanks,GregVista 64 bit 8MB ram Greg Moorehttp://www.precisionmanuals.com/images/forum/747400.jpghttp://www.precisionmanuals.com/images/for...argo_hauler.gif

I do and highly recommend it. It will not harm the game. However, I believe FSX uses software-accelerated Direct3D for rendering and SLI works best when the game uses hardware-accelerated Direct3D. I've tried it both ways and see little or no difference in graphic quality or performance. However, I saw a massive increase in performance in 3DMark Vantage benchmarks. SLI was much, much better. With your system, you might see better performance too as you have recent hardware from Nvidia. I have two 768MB 8800GTX video cards. I'm thinking you had a typo in your signature whereas you have 8GB of RAM vs 8MB? I hope so anyway! Jim

HelloSo you are saying thatFSX benefits from SLI.Quote "However, I believe FSX uses software-accelerated Direct3D for rendering"Then you say Quote "SLI works best when the game uses hardware-accelerated Direct3D."If as you maintain "FSX uses software-accelerated Direct3D"then SLI will not work to its best effect or have no benefit.Or have i missed something ?

No, you missed nothing. Hope I didn't confuse you too much.Jim

Some motherboards revert from PCI-e x16 to PCI-e x8 when in SLI mode. Could this cause poorer FSX performance than one video card?ArtBiostar TF560-A2+, Athlon 64X2-6000+, 4GB RAM, Geforce 8800GTS-320MB, 500W PSU, 250GB HD, FSX(SP1-SP2), Audigy SE sound, Vista Home Premium 32 bit, CH Yoke & Pedals, 22" WS LCD monitor

Yes, 8GBGreg Moorehttp://www.precisionmanuals.com/images/forum/747400.jpghttp://www.precisionmanuals.com/images/for...argo_hauler.gif

"Some motherboards revert from PCI-e x16 to PCI-e x8 when in SLI mode. Could this cause poorer FSX performance than one video card?"I would assume it would cause poorer performance. I would strongly suggest anyone running Nvidia cards in SLI mode also have a Nvidia NForce MB. I found the following link interesting and might be an answer - http://forums.ngemu.com/hardware-discussio...dly-please.html. If you don't have an Nvidia MB or a very good PSU (I have a 1K PSU) you may encounter CTD or performance problems running in SLI. Jim