How can set param to encode 600mb 4K H.264?

The maximum code rate set by ffmpeg h264_nvenc encoder for 4K coding is 144 mb. Program error occurs when the code rate exceeds 144 mb:[h264_nvenc @ 0000017e632de440] InitializeEncoder failed: invalid param (8).
How to set the bitrate to 500mb in 4K H.264 coding?

ffmpeg.exe -i L:\1.mp4 -c:v h264_nvenc -b:v 600000k -g 1 -c:a aac -f mp4 l:\test500mb.mp4 -y
ffmpeg version 4.0.2 Copyright © 2000-2018 the FFmpeg developers
built with gcc 7.3.1 (GCC) 20180722
configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
libavutil 56. 14.100 / 56. 14.100
libavcodec 58. 18.100 / 58. 18.100
libavformat 58. 12.100 / 58. 12.100
libavdevice 58. 3.100 / 58. 3.100
libavfilter 7. 16.100 / 7. 16.100
libswscale 5. 1.100 / 5. 1.100
libswresample 3. 1.100 / 3. 1.100
libpostproc 55. 1.100 / 55. 1.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from ‘L:\1.mp4’:
Metadata:
major_brand : qt
minor_version : 512
compatible_brands: qt
encoder : Lavf58.12.100
Duration: 00:01:08.60, start: 0.000000, bitrate: 18142 kb/s
Stream #0:0(eng): Video: hevc (Main) (hev1 / 0x31766568), yuv420p(tv, unknown/bt2020/unknown), 3840x2160 [SAR 1:1 DAR 16:9], 11996 kb/s, 25 fps, 25 tbr, 12800 tbn, 25 tbc (default)
Metadata:
handler_name : DataHandler
Stream #0:1(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, 7.1, s16, 6144 kb/s (default)
Metadata:
handler_name : DataHandler
Stream mapping:
Stream #0:0 -> #0:0 (hevc (native) -> h264 (h264_nvenc))
Stream #0:1 -> #0:1 (pcm_s16le (native) -> aac (native))
Press [q] to stop, [?] for help
[h264_nvenc @ 000001d9a0ec3d00] InitializeEncoder failed: invalid param (8)
Error initializing output stream 0:0 – Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
[aac @ 000001d9a0e7aa00] Qavg: 45469.547
[aac @ 000001d9a0e7aa00] 2 frames left in the queue on closing
Conversion failed!

Hi flhcd,
Thanks for reporting this issue. This is a bug in our driver code and we will fix this in future driver series.
For reference, this is tracked internally as 200535668.

Thanks.