First of all what is ANTIALIASING and is it good or bad. Also this is for Techguy if he reads this. I ended up getting an NVIDIA 6600 AGP for my older system and then got the PCI EXPRESS for my new system thats SLI. Anyways on the AGP card if VSYNC is enabled in DOOM 3 it tears like you mentioned in SLI setups, but with the SLI Setup with one card it still tears. You said that SLI didnt support VSYNC but I dont think AGP or SLI PCIEXPRESS either one works well with VSYNC is that just an ATI thing or what. Also the game I tested this on was DOOM 3 so any feedback would be appreciated.
antialiasing In computer graphics, antialiasing is a software technique for diminishing jaggies - stairstep-like lines that should be smooth. Jaggies occur because the output device, the monitor or printer, doesn't have a high enough resolution to represent a smooth line. Antialiasing reduces the prominence of jaggies by surrounding the stairsteps with intermediate shades of gray (for gray-scaling devices) or color (for color devices). Although this reduces the jagged appearance of the lines, it also makes them fuzzier. Another method for reducing jaggies is called smoothing, in which the printer changes the size and horizontal alignment of dots to make curves smoother. doom 3 does support vsync you can pause the game and enable it, and it should stop the tearing. unless it's application controlled, go to your card properties click performance and quality settings. you will see vsync uncheck the application controlled box and set it to on. try to run the game again and see what this does. as long as you have everything set up right on your sli rig in the bios you turned off sli to single card. it should be the same. and no vsync is not just a ati thing lol.