Hi all,
This patch 3424 Beta Patch DID work perfectly, it now does not, option is greyed out, I reinstalled the patch and still not allowing me to select the FAST VIdeo Rendering Technology, this made an amazing difference in my Video Rendering times.
Please see attachments, which includes DxDiag, I have no issues running PD16 With my Hardware etc either, plus this is a newly formatted Win10Pro install
Any ideas folks?

To add to this it definitely something in the profile thats not allowing me to use it, heres the profile
&
<Class>MPEG-4 AVC
<Name>2K @ 60FPS - 80000 BITRATE
<Description>2K @ 60FPS - 80000 BITRATE
<Output FileName>
<DescID>11920
<NameID>11983
<Group>2
<File Format Class>11
<Video Format Class>8
<Audio Format Class>10
<Stream Flag>3
<Field Order>0
<Attribute>10040083
<Video BitRate>80000000
<Min BitRate>60000000
<Max BitRate>80500000
<Video Quality>0
<Video Width>2560
<Video Height>1440
<Frame Rate>60.000000
<Profile Level>65380
<Pattern>IBBPBBPBBPBBP
<Pre Processing>0
<Resize>1
<Flip Video>0
<Speed Quality Indicator>6
<Interlacing>0
<Encoder Mode>0
<App Type>2
<Dynamic GOP>1
<Deblock>1
<EntryMode>1
<Encoder Type>32
<Audio Layer>2
<Audio Mode>2
<Audio BitRate>384000
<Audio Channels>2
<Audio SamplesPerSec>1
<Audio BitsPerSample>1
<Misc>0
<SamplesPerFrame>0
&&
It definitely worked before but not it is not, below is the media info from a previously rendered file using this profile:
General
Complete name : E:\FINAL VIDEO\VIDEO 13.mp4
Format : MPEG-4
Format profile : Sony PSP
Codec ID : MSNV
File size : 13.8 GiB
Duration : 25mn 0s
Overall bit rate : 79.2 Mbps
Encoded date : UTC 2018-10-30 14:50:53
Tagged date : UTC 2018-10-30 14:50:53
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L5.1
Format settings, CABAC : Yes
Format settings, ReFrames : 2 frames
Format settings, GOP : M=3, N=13
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 25mn 0s
Source duration : 25mn 0s
Bit rate : 78.8 Mbps
Width : 2 560 pixels
Height : 1 440 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 60.000 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.356
Stream size : 13.8 GiB (100%)
Source stream size : 13.8 GiB (100%)
Language : English
Encoded date : UTC 2018-10-30 14:50:53
Tagged date : UTC 2018-10-30 14:50:53
mdhd_Duration : 1500394
Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 25mn 0s
Source duration : 25mn 0s
Bit rate mode : Constant
Bit rate : 384 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz
Compression mode : Lossy
Stream size : 68.7 MiB (0%)
Source stream size : 68.7 MiB (0%)
Language : English
Encoded date : UTC 2018-10-30 14:50:53
Tagged date : UTC 2018-10-30 14:50:53