Hi, so i have had a GTX 580 for a while now and i had ordered another one (same one) to SLI them, Doing so my computer became very unstable when in SLI, even with nothing running my system bogs down for no reason, and this is a fresh install of windows 8 pro x64
i had updated drivers and such, but one thing i did do, is swaped the cards ran the individualy, my original card works great by its self, but the new card by its self lags, and bogs system down like its been doing in SLI.
So does this mean that that card is defective? Thanks
You'll also want to re-install the drivers, clean sweep, each time you swap the config around to be sure.
Check to make sure that you have enough power, these things are rated at ~250W each, when not overclocked, and theoretically can pull up to 375W from the supply.
If that single card is showing signs of issues, make sure it isn't overclocked or over temp when you run it. Use MSI Afterburner or Hardware Monitor to keep an eye on temps. If it was abused it might need the heatsink compound replaced, or just be damaged.