This is what my latest logfile looks like and as far as I can tell GPU acceleration is enabled so that's why I wonder why the GPU util isn't higher during a ripping process.
Not sure if it was mentioned in the logfile somewhere already but I'm using a fresh install of the latest Nvidia drivers (353.30)
DVDFab 9.2.0.2 (2015/07/13 22:54:11)
0m 00.03s: Init Public log : enabled.
0m 00.03s: Init Private log : finish.
0m 00.03s: App info: 2015-6-10
0m 00.03s: App info: 9.2.0.2 9202 Official
0m 00.03s: Init CrashReportSettings : enabled.
0m 00.03s: Init DVDInfo_Log : enabled.
0m 00.03s: Init Qt_Log : disabled.
0m 00.07s: Profile Manager :: Begin Load Profile
0m 00.07s: Qt Translator file load success
0m 00.07s: App info: client type 2.
0m 00.08s: MobilePlay load: preload successful.
0m 00.12s: MobilePlay load: Load successful.
0m 00.12s: Init process: Transfer settings successful.
0m 00.12s: info: check logpath= C:/Users/Richard/Documents/DVDFab9/Log/
0m 00.13s: info: _check_gpu is running ...
0m 00.24s: info: check_gpu run successful
0m 00.24s: info: recommand= 56, Shrink support= 0, enable= 0, cuda_cap= 1 , cpu_count= 4
0m 00.24s: GPU check: GPUAccelerate-4159
0m 00.24s: GPU check: GPUAccelerate setting-56, 56
0m 00.24s: GPU check: CUDA cap-1
0m 00.24s: GPU check: Support coreavc decode-0
0m 00.24s: GPU check: Lighting shrink status-0, 0
0m 00.24s: GPU check: Graphics info 1: NVIDIA GeForce GTX 980 Ti : 10.18.13.5330 : 5.2
0m 00.25s: Init process: Load config successful.
0m 00.25s: Init process: Windows os type is 64bit System Windows 7.
0m 00.25s: Init process: command line in is "G:\"
0m 00.25s: bTimeoutReturn=0
0m 00.25s: Init process: there is another app running and exit.
0m 00.47s: Profile Manager :: End Load Profile
55m 21.90s: got agid 0
55m 21.93s: sent host cert chal
55m 21.94s: got drive cert chal
55m 21.94s: BEC 1
55m 21.94s: DRIVE_VENDOR 0x0074
55m 21.99s: got drive key
55m 21.99s: got host key signature
55m 21.99s: verified drive signature
55m 21.99s: verified host signature
55m 22.04s: sent host signature and key point
55m 22.04s: got bus key
55m 24.90s: D CD1F2757
55m 24.90s: got vuk
55m 25.22s: got unit key 1
55m 30.44s: got bdmv
55m 34.86s: got extended bdinfo
55m 34.86s: opened blu-ray
55m 35.27s: Source manager: open successful.
55m 35.38s: Work manager: create Converter work 1 with source 1 and uiinfo 1( title 100 ).
55m 35.69s: ========WorkAttr::SetSource=======
55m 35.69s: Source Video Size Original : 1920 x 1080
55m 35.69s: Source Video Size Display : 1920 x 1080
55m 35.69s: Source Video FPS : 24000 / 1001
55m 35.69s: Source Video Bitrate : 1200
55m 35.69s: Source Audio Bitrate : 0
55m 35.69s: Source Audio Channels : 8
55m 35.69s: Source Audio Volume : 100
55m 35.69s: Work Profile : AVI
55m 46.24s: UILog:OnMsgToolbar_Start
55m 46.24s: UILog:Msg Start : ready start
55m 46.24s: UILog:Msg Start : start test run work
55m 46.26s: UILog:Msg Start : run work
55m 46.26s: UILog:Run current Work.
55m 46.26s: UILog:Begin work Converter.
55m 46.26s: UILog:Begin work copy or converter.
55m 46.26s: Start check Blu-ray Ripper (3D Plus) register status.
55m 46.26s: End check Blu-ray Ripper (3D Plus) register status: Enable
55m 46.26s: UILog:start running at thread.
55m 46.26s: UILog:return flag at start running at thread ok.
55m 46.27s: OPList at BD Converter : (4113.2),(4352.4),(4616.8)
55m 46.27s: Blu-ray Converter (3D Plus) check watermark flag: 0
55m 46.27s: ------------------ convert work begin(1/1) ------------------
55m 46.27s: start process(1/1)
55m 46.27s: info: create config(bluray2video)
55m 46.27s: info: crop value after clone: left = 0 right= 0 top=0 bottom=0 enable=0 mode=0
55m 46.28s: info: use profile(AVI)
55m 46.28s: info: bluray playlist(100),angle(0),chapter(1->12),BDAV(no)
55m 46.28s: info: 3D working_mode(disable), 3D format(sbs_lef_right)
55m 46.28s: info: stream input@ Video(4113)[codec(h264) size(1920*1080) fps(24000/1001) interlace(0) duration(6284)sec opcode(compress)]
55m 46.28s: info: perset file config OK !
55m 46.28s: info: set output video frame_rate(24000/1001)
55m 46.28s: info: stream output Video(4113)[codec(h264) size(1920*1080) fps(24000/1001) interlace(0) bitrate(4972) duration(6284)sec]
55m 46.29s: info: stream input@ Audio(4352)[codec(dca) channels(8) sample(48000) bitrate(0) bitdepth(24) opcode(remove_hd)]
55m 46.29s: info: stream output Audio(4352)[codec(dca) channels(8) sample(48000) bitrate(0) bitdepth(24) opcode(remove_hd)]
55m 46.29s: info: stream input@ SubPicture(4616)[codec(pgssub) language(Swedish) opcode(render)]
55m 46.29s: info: SubMode(Render) -- Display Only forced Subtitle(false)
55m 46.29s: UILog:MsgWork:WorkStatus_Start
55m 46.29s: CUDA GPU acceleration for video decoding enabled
55m 46.35s: info: ex process path= C:/Program Files (x86)/DVDFab 9/fabcore.exe
55m 46.38s: info: h264_encode: encode param profile(1) level(40) bitrate(4972) crf(-1) interlace(0)
55m 46.38s: info: connect to sub render filter success.
55m 46.39s: info: processing source(00109.m2ts)
95m 26.52s: info: bluray read data end
95m 32.66s: ------------------ convert work finished ------------------
95m 33.66s: UILog:MsgWork:current work finish : 3
95m 38.06s: UILog:Run Work to end.
95m 38.22s: DriveX msg: remove media in driveX G.
95m 38.45s: Source manager:open source flag:1,0,1,1,1
98m 57.40s: Warning : Null Data at Work
98m 59.42s: Source manager:open source flag:1,1,1,1,1
99m 03.99s: Exit process: stop running.
99m 03.99s: Exit process: preview pfn_releaseplayer end
99m 04.02s: Exit process: preview pfn_deinit end
99m 04.02s: Exit process: preview FreeLibrary end
99m 04.02s: Exit process: finish MainUI.
99m 04.05s: Exit process: finish FreePref.
99m 04.05s: Exit process: finish AVEditWrap Release.