i did that too as well in OMP and the same thing happened
example:
http://www.twitch.tv/mikephlurry/b/336667192#
obs is set to 1024x768 as well as source configure
dxtory video is set to 1024x768 as well as output
this is what comes up
Open Broadcaster Software v0.421a - 32bit (´・ω・`)
-------------------------------
CPU Name: Intel(R) Core(TM) i7-3720QM CPU @ 2.60GHz
CPU Speed: 2594MHz
Physical Memory: 4095MB Total, 4095MB Free
stepping id: 9, model 10, family 6, type 0, extmodel 1, extfamily 0
------------------------------------------
Adapter 1
Video Adapter: Intel(R) HD Graphics 4000
Video Adapeter Dedicated Video Memory: 67108864
Video Adapeter Shared System Memory: 1711276032
=====Stream Start=====================================================================
Base resolution: 1024x768
Output resolution: 1024x768
------------------------------------------
Loading up D3D10...
------------------------------------------
Audio Encoding: AAC
bitrate: 128
------------------------------------------
Video Encoding: x264
fps: 30
width: 1024, height: 768
quality: 5
preset: veryfast
i444: no
max bitrate: 1500
buffer size: 1500
------------------------------------------
Total frames rendered: 93, number of frames that lagged: 25 (26.88%) (it's okay for some frames to lag)
=====Stream End=======================================================================
=====Stream Start=====================================================================
Base resolution: 1024x768
Output resolution: 1024x768
------------------------------------------
Loading up D3D10...
------------------------------------------
Audio Encoding: AAC
bitrate: 128
------------------------------------------
Video Encoding: x264
fps: 30
width: 1024, height: 768
quality: 5
preset: veryfast
i444: no
max bitrate: 1500
buffer size: 1500
------------------------------------------
Total frames rendered: 963, number of frames that lagged: 3 (0.31%) (it's okay for some frames to lag)
=====Stream End=======================================================================
Send Buffer Size: 4096
=====Stream Start=====================================================================
Base resolution: 1024x768
Output resolution: 1024x768
------------------------------------------
Loading up D3D10...
------------------------------------------
Audio Encoding: AAC
bitrate: 128
------------------------------------------
Video Encoding: x264
fps: 30
width: 1024, height: 768
quality: 5
preset: veryfast
i444: no
max bitrate: 1500
buffer size: 1500
------------------------------------------
Total frames rendered: 2692, number of frames that lagged: 1 (0.04%) (it's okay for some frames to lag)
Number of b-frames dropped: 0, Number of p-frames dropped: 0
=====Stream End=======================================================================
Profiler results:
==============================================================
frame - [100%] [avg time: 6.408 ms] [avg calls per frame: 1] [children: 96.2%] [unaccounted: 3.81%]
| scene->Preprocess - [35.8%] [avg time: 2.297 ms] [avg calls per frame: 1]
| video encoding and uploading - [60.3%] [avg time: 3.867 ms] [avg calls per frame: 1] [children: 24.3%] [unaccounted: 36.1%]
| | CopyResource - [0.749%] [avg time: 0.048 ms] [avg calls per frame: 0]
| | conversion to 4:2:0 - [12%] [avg time: 0.767 ms] [avg calls per frame: 0]
| | call to encoder - [11.5%] [avg time: 0.739 ms] [avg calls per frame: 0]
==============================================================