I wanted to find out what software configuration would yield the highest performance when streaming. So I did.
Preface:
OpenBroadcasterSoftware (OBS) is beta software that has only recently been developed. It is a free and open source alternative to Xsplit. It can be downloaded @ http://obsproject.com/
Aero is the desktop composition module in Windows 7 responsible for the fancy "glass" window borders and taskbar. Most streaming programs and guides reccomend you to turn it off. However, my tests don't completely agree.
Test settings:
Stream resolution of 960x600 and a framerate of 30.
1700 video bitrate, 10 quality, "veryfast" preset, 128 audio bitrate (AAC)
TF2 running in a native resolution noborder window (1680x1050).
Test procedure:
Open programs needed for test.
Open TF2.
Begin streaming.
Run three "timedemo"s in TF2 to benchmark performance. "Timedemo" is a command that lets you play a demo, and afterward the game prints a line with some performance statistics to the console. A "timedemo" always plays with a host_framerate of 66. The same demo file was used for every test.
Data set:
Each scenario was run three times (more if anomalies were observed), and the results averaged.
Results:
Sorted by performance (highest at top)
Control (Not streaming, Aero off)
AVERAGE: 41486 frames 144.422 seconds 287.26 fps ( 3.48 ms/f) 31.2 fps variability
Control (Not streaming, Aero on)
AVERAGE: 41486 frames 156.161 seconds 265.66 fps ( 3.76 ms/f) 36.1 fps variability
OBS Window Capture & Aero
AVERAGE: 41486 frames 177.971 seconds 233.11 fps ( 4.29 ms/f) 40.5 fps variability
OBS w/ Dxtory & No Aero
AVERAGE: 41486 frames 188.321 seconds 220.29 fps ( 4.54 ms/f) 45.7 fps variability
OBS w/ Dxtory & Aero
AVERAGE: 41486 frames 193.119 seconds 214.83 fps ( 4.66 ms/f) 42.9 fps variability
XSplit w/ Dxtory & Aero
AVERAGE: 41486 frames 212.022 seconds 195.68 fps ( 5.11 ms/f) 42.3 fps variability
Xsplit w/ Dxtory & No Aero
AVERAGE: 41486 frames 214.834 seconds 193.12 fps ( 5.18 ms/f) 42.9 fps variability
OBS Window Capture & No Aero
AVERAGE: 41486 frames 220.966 seconds 187.75 fps ( 5.32 ms/f) 49.3 fps variability
XSplit Screen region & Aero
AVERAGE: 41486 frames 252.391 seconds 164.38 fps ( 6.08 ms/f) 46.2 fps variability
XSplit Screen region & No Aero
AVERAGE: 41486 frames 257.593 seconds 161.05 fps ( 6.21 ms/f) 60.4 fps variability