I just tried that and the same thing happens: Almost 80+% CPU usage, no noticeable GPU usage and about 9 FPS. I downloaded Davinci Resolve and got 500 FPS for h.264 1080P. I think I am going to have to look more seriously at that editor. I have been using Vegas Video since the early days with and before Sony. This is really disappointing.

Historically Vegas has been great. This started sometime around the end of last year. Regressing the NVIDIA Drivers did not help.

Something is strange with your system then as this isn't a general known issue with VP 23.

Can you try rendering one of the benchmarks in my signature (both known good projects)? Render to h264 with NVENC template.

If you still see no activity try a reset of VEGAS and then please test again.
https://www.vegascreativesoftware.info/us/forum/faq-how-can-i-reset-vegas-pro-to-default-settings--104646/

I'm sure a clean install of Resolve or Premiere would work with your GPU; the same is true of VEGAS.

I got 23 FPS after clearing the cache and running Vegas pro 20 Ad Benchmark. I don't see any GPU usage in process explorer, but I didn't in Davinci either and I got 500 FPS there. I tried my project again and it slows to around 9 FPS, still.

This was a clean install of Vegas. I purchased this computer late last year and installed vegas 23 directly on it.

VP 20 ad benchmark has a ton of Fx and is quite involved- you can see the results spreadsheet for how your system compares to similar hardware. Is it in the normal range for render times?

For your project if it's slower than even the very challenging VP 20 ad, there's likely something causing a bottleneck. The GPU seems like it is working but probably waiting forever to get frames to encode? Some possible slowdown causes could be AI-powered Fx, having events overlap themselves (transitions from media A to media A vs media A and media B), 32-bit mode, etc.

The project I was trying to render only has simple standard crossfade transitions and occasional overlay titles. That is it. 2 video tracks, 1 audio track. Source video is mp4 content from a Sony camera. I have been using this setup for nearly a decade. The dramatic slowdown is new. The end render is for YouTube upload.

DaVinci get 500+ FPS with the same content.

If you download the free app "mediainfo", and run it on one of those video files from your sony camera, then copy and paste the report it generates here for us, it'll give us much more insight into the exact codecs your content is using, and we might be able to better tell what is causing your bottleneck here by knowing that info.

It could be a limitation, or an incorrect setting in preferences that is causing this. Anything from the file i/o hardware decoder to the video tab's GPU acceleration device to dynamic RAM preview (do not touch this if you haven't already).

Dramatic slowdowns with crossfades is new since 22. If you can share MediaInfo and maybe even a sample .veg (no media) I can test it here on my 4060- I shoot all mp4 with Sony cameras.

General
ID                                       : 0 (0x0)
Complete name                            : D:\Projects for You Tube\Projects\Shop Miscellany #27\01229.MTS
CompleteName_Last                        : D:\Projects for You Tube\Projects\Shop Miscellany #27\01264.MTS
Format                                   : BDAV
Format/Info                              : Blu-ray Video
File size                                : 7.78 GiB
Duration                                 : 24 s 497 ms
Overall bit rate mode                    : Variable
Overall bit rate                         : 2 729 Mb/s
Maximum Overall bit rate                 : 28.0 Mb/s
Frame rate                               : 59.940 FPS
Recorded date                            : 2026-03-01 11:03:16-07:00
Writing application                      : Sony HDR-CX455

Video
ID                                       : 4113 (0x1011)
Menu ID                                  : 1 (0x1)
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L4.2
Format settings                          : CABAC / 2 Ref Frames
Format settings, CABAC                   : Yes
Format settings, Reference frames        : 2 frames
Format settings, GOP                     : M=1, N=30
Format settings, Slice count             : 4 slices per frame
Codec ID                                 : 27
Duration                                 : 24 s 24 ms
Bit rate mode                            : Variable
Bit rate                                 : 2 621 Mb/s
Maximum bit rate                         : 26.0 Mb/s
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 59.940 (60000/1001) FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 21.088
Stream size                              : 7.33 GiB (94%)
IrisFNumber                              : 2.600000

Audio
ID                                       : 4352 (0x1100)
Menu ID                                  : 1 (0x1)
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Commercial name                          : Dolby Digital
Codec ID                                 : 129
Duration                                 : 24 s 32 ms
Bit rate mode                            : Constant
Bit rate                                 : 256 kb/s
Channel(s)                               : 2 channels
Channel layout                           : L R
Sampling rate                            : 48.0 kHz
Frame rate                               : 31.250 FPS (1536 SPF)
Compression mode                         : Lossy
Stream size                              : 751 KiB (0%)
Service kind                             : Complete Main
Dialog Normalization                     : -31 dB
compr                                    : -0.28 dB
Dialogue normalization, average          : -31 dB
Dialogue normalization, minimum          : -31 dB
Dialogue normalization, maximum          : -31 dB

Text
ID                                       : 4608 (0x1200)
Menu ID                                  : 1 (0x1)
Format                                   : PGS
Codec ID                                 : 144
Duration                                 : 23 s 458 ms

Here is a link to a simple project:

https://drive.google.com/file/d/182anOemw484o1znEmOkhfqDpne4ef6yf/view?usp=sharing

Thanks Robert, will take a look!

Actually is it possible to share one sample media somewhere on Drive? I use newer cameras that are XAVCS (mp4) rather than MTS.

Replacing the media with my own MTS AVC HD media I'm getting better performance so far.

This is with my laptop, a much weaker system than what you have.

I just tried your project with my System:

NVIDIA Systeminformationen-Bericht erstellt am: 03/04/2026 10:06:43
Version der NVIDIA App: 11.0.6.383
Betriebssystem: Microsoft Windows 11 Pro, Version 10.0.26200
DirectX-Laufzeitversion: DirectX 12
Treiber: Studio-Treiber - 591.44 - Thu Dec 4, 2025
CPU: Intel(R) Core(TM) i7-14700
RAM: 32.0 GB
Speicher (2): SSD - 3.6 TB,SSD - 953.9 GB

Grafikkarte
GPU: NVIDIA GeForce RTX 4070
Direct3D-Funktionsebene: 12_1
CUDA-Kerne: 5888
Grafik-Taktfrequenz: 2475 MHz
Resizable BAR: Ja
Speicher-Datenrate: 21.00 Gbps
Speicherschnittstelle: 192-Bit
Speicherbandbreite: 504.048 GB/s
Gesamter verfügbarer Grafikspeicher: 27467 MB
System-Videospeicher: Nicht anwendbar
Gemeinsam genutzter Systemspeicher: 15185 MB
Dedizierter Videospeicher: 12282 MB GDDR6X
Video-BIOS-Version: 95.04.3e.08.dc
Geräte-ID: 10DE 2786 513A1028
Teilenummer: G141 0345
IRQ: Nicht benutzt
Bus: PCI Express x16 Gen4

Anzeige (2): HP Inc. HP 24f
Auflösung: 1080p, 1920 x 1080 (nativ)
Bildwiederholfrequenz: 60 Hz
Desktop-Farbtiefe: Maximum (32 Bit)
HDCP: Unterstützt

Anzeige (1): Philips PHL 27M1F5800
Auflösung: 3840 x 2160 (nativ)
Bildwiederholfrequenz: 120 Hz
Desktop-Farbtiefe: Maximum (32 Bit)
HDCP: Unterstützt

I replaced your MTS files with my own created by a Sony Camera. Only difference: As I am in German my frame arte is 50 fps and not 59fps. Rendering to Internet H.264 NVENC 50 GPU is at 54%, CPU at 24%. Rendering speed is between 90 and 200fps. In average over 100fps. Rendertime for the complete project is 14:27. So in average over 100 fps. So there must be something wrong in your setup why VP is not using the GPU.

Roger & Harold - Problem is you are not comparing the same source material. Although Robert's mts file doesn't look unusual maybe it is harder for Vegas to decode which slows rendering down. It's progressive with AC3 audio. Were your substitute files similar?

There are three variables to control. The project, the settings and the media. We've concluded the project isn't the issue.

@EricLNZ I don't know if the difference in file types matters. I did ask for the exact files but failing that I used what I had which were from a 2010 era Panasonic camera. They are progressive 720p with AC3 audio.

I see GPU activity for decoding, encoding and 3D.
My preferences/video use the NVIDIA 4060 and preferences/file io are on default settings.

General
ID                             : 0 (0x0)
Complete name                  : m2ts
Format                         : BDAV
Format/Info                    : Blu-ray Video
File size                      : 8.16 MiB
Duration                       : 4 s 485 ms
Overall bit rate mode          : Variable
Overall bit rate               : 15.3 Mb/s
Maximum Overall bit rate       : 18.0 Mb/s
Frame rate                     : 29.970 FPS

Video
ID                             : 4113 (0x1011)
Menu ID                        : 1 (0x1)
Format                         : AVC
Format/Info                    : Advanced Video Codec
Format profile                 : High@L4
Format settings                : Frame doubling / 1 Ref Frames
Format settings, CABAC         : No
Format settings, Reference fra : 1 frame
Frame mode                     : Frame doubling
Format settings, GOP           : M=1, N=15
Codec ID                       : 27
Duration                       : 4 s 488 ms
Bit rate mode                  : Variable
Bit rate                       : 14.5 Mb/s
Maximum bit rate               : 16.6 Mb/s
Width                          : 1 280 pixels
Height                         : 720 pixels
Display aspect ratio           : 16:9
Frame rate                     : 29.970 (30000/1001) FPS
Standard                       : NTSC
Color space                    : YUV
Chroma subsampling             : 4:2:0
Bit depth                      : 8 bits
Scan type                      : Progressive
Bits/(Pixel*Frame)             : 0.523
Time code of first frame       : 00:00:00:00
Stream size                    : 7.76 MiB (95%)
Color range                    : Limited

Audio
ID                             : 4352 (0x1100)
Menu ID                        : 1 (0x1)
Format                         : AC-3
Format/Info                    : Audio Coding 3
Commercial name                : Dolby Digital
Codec ID                       : 129
Duration                       : 4 s 512 ms
Bit rate mode                  : Constant
Bit rate                       : 192 kb/s
Channel(s)                     : 2 channels
Channel layout                 : L R
Sampling rate                  : 48.0 kHz
Frame rate                     : 31.250 FPS (1536 SPF)
Compression mode               : Lossy
Stream size                    : 106 KiB (1%)
Service kind                   : Complete Main
Dialog Normalization           : -31 dB
compr                          : -11.02 dB
dialnorm_Average               : -31 dB
dialnorm_Minimum               : -31 dB
dialnorm_Maximum               : -31 dB

@robert-weitkamp I wonder if just repackaging your mts clips into mp4 containers might help Vegas process them faster. Many folks here use ShutterEncoder to do things like that. I'd be happy to try the script I use on your clips if you can throw them into a zip on a google drive.

Might be worth looking into which decoders are being used on his system to decode these files also. If he has legacy enabled, for instance.

As another test, I took the output of Vegas render (.mp4) took that file and split it in a bunch of pieces with 1s crossfades. The file started rendering at 400 FPS and then slowed to 4 FPS. It would speed up after 15 or so seconds only to slow again a 30 seconds later. This repeats until I cancelled the render. Average overall speed 175 FPS. The slow downs do not coincide with the transitions and only happen 3 or so times when there are 6 transitions.

Just tried some of my own mts clips swapped into @robert-weitkamp project. I made a bunch of 5 sec long clips and they rendered real quick with allot of event looping. Lengthening them to 1 minute long mts clips got much less looping and slowed the render down to about 15 to 20 fps. The mts clips showed no decoding activity. Checking legacy avc was a little quicker but still no decoding activity. The 1st Title clip was mp4 and that did show decoding activity and rendered at about a 10x quicker fps. Transcoding all the mts to avc/mp4 also rendered 10x quicker. My clips did not benefit from simple repackaging but they're probably not exactly the same as as Robert's so it might still be worth a try.

Btw, I did this testing on an Utra 5080 and noticed about 40% compute-engine utilization on the igpu even though it wasn't selected for anything... so I disabled it's driver to make the system look more like a Ryzen.