Both of you guys are running on a processor that features an integrated graphics chipset. Could you guys test if you're getting the same error when you run on that integrated graphics chipset?
This is going to take some playing around to figure out... I enabled the integrated graphics, still crashed (note: no reboot; I just noticed that the monitor output wasn't force-enabled for Active Sync on Windows 7). I thought it might have to do with using SLI/Surround on the nVidia side, so I disabled that... OBS didn't crash on startup. Then I re-enabled it, and OBS didn't crash on startup. O_o So something I did in between those steps fixed whatever was going wrong.
I'm going to try rebooting and see if I can reproduce the error, and then backtrack again from there.
Edit:
Okay, it seems like at least in my case, the crash happens whenever I have my desktop resolution in nVidia Surround set to the "Bezel Corrected" (ie, a very non-standard) resolution I had set up. 5040x1050 works fine; 5296x1050 crashes.
Edit 2:
Changing OBS's output resolution to a standard resolution (ie, 1600x900) also seems to fix it; no crash using the bezel-corrected resolution after manually entering the resolution in the settings in OBS.