Same here

@wwaag +1

Let me guess--you have added an effect or scaling to your 4k event.

In theory this might be caused by long GOPs.
Unfortunately, I do not know how Vegas processing the reverse internally so I cannot be sure.

Hello Guys,

Actually its building a proxy. Seen on the bottom bar. It takes around 40 mins for this 8 sec clip. The files are 4k 100Mbps 30fps. Editing on a native 4K 30fps timeline so no upscaling or downscaling going on either. No effect applied to the clip. Puzzled.

Something is definitely wrong with your system or project setup. Here's an example of a 9 sec 4K 100mbps video file creating a proxy. It's close to or even quicker than realtime--certainly not 40 min. The proxy is only 1280 x 720 at 24fps, so the conversion is very quick.

Suggest that you upload a screengrab of your project settings dialog.

But i should also state that my system is only a core i3 @3.10 Ghz. OS and Vegas runs from an SSD. Independent 7200rpm drives of 2TB each for footage and for renders drive. There's only Vegas/DVD Arch/Adobe Flash/3ds Max installed on the system (workstation is dedicated only for editing, no other silly programs, no internet, games and such). Backup is on a 4TB drive. So total of 4 drives. 16 GB Ram. No graphics card. Running on Intel Graphics HD530 on board. I edit using a dual 1080p monitor setup. My HDDs are all only 25% full (75% is free), except for the backup drive which comes into play only during backups of-course.

There's no way to put up my jpg screenshot of my project settings thanks to forum features here 😃.

But pretty much all of the settings are exact footage matched 3840x2160p, progressive only, 29.976 fps with a square pixel aspect ratio. Ive been working with Vegas for 9 years now. Ive explored a lot of the internal menus etc over these years though i wouldn't call myself an expert.

Renders run reasonably OK for a core i3. Play back is horrible. Im willing to invest in a good graphics card but opinions are so varied from what i see around that Vegas will never use the card for playback. Also my processor is at 50% only when im playing back from the timeline so im guessing for "edit preview" i don't need a faster processor. Ive seen Vegas run on a core i7 and it doesn't smoke this one out, except that the render time is much faster, which is why im still using my core i3 6100. Currently all my 4k files are auto converted to 720p when i drop them on the timeline. Yet i cant watch my preview at anything more than DRAFT HALF. DRAFT FULL works if i just put the footage on the timeline with no filters or color correction. Slightly color corrected clips etc and i have to use only DRAFT HALF.

There's no way to put up my jpg screenshot of my project settings thanks to forum features here 

https://www.vegascreativesoftware.info/us/forum/important-information-required-to-help-you--110457/ B-5:

Press Ctrl + Shift + Esc (to open task manager) during the 30 mins interval while Vegas doing 'reverse' and on Performance tab check CPU/GPU/Disks utilization. I'd say your system a bit low end for Video Editing.

Do you have any anti virus installed? Can you try to turn it off while testing? It might be configured to check the video files (it should not usually) and with low end CPU this might slows down the whole process too much.

If you are also working on a 4k proxied to 720p timeline with 30fps files. Whats the best preview resolution you can choose for your timeline playback. WITHOUT stuttering or frame drops. And what processor do you use plz ?

My own footage is 1080-60p. For testing I downloaded 4K-25p file with that info (I excluded audio info):
 

General
Complete name                            : C:\Temp\C0049.MP4
Format                                   : XAVC
Codec ID                                 : XAVC (XAVC/mp42/iso2)
File size                                : 762 MiB
Duration                                 : 1 min 3 s
Overall bit rate mode                    : Variable
Overall bit rate                         : 100 Mb/s
Encoded date                             : UTC 2018-02-25 17:16:35
Tagged date                              : UTC 2018-02-25 17:16:35

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L5.1
Format settings                          : CABAC / 2 Ref Frames
Format settings, CABAC                   : Yes
Format settings, Reference frames        : 2 frames
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 1 min 3 s
Bit rate mode                            : Variable
Bit rate                                 : 98.3 Mb/s
Maximum bit rate                         : 100.0 Mb/s
Width                                    : 3 840 pixels
Height                                   : 2 160 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 25.000 FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.474
Stream size                              : 748 MiB (98%)
Encoded date                             : UTC 2018-02-25 17:16:35
Tagged date                              : UTC 2018-02-25 17:16:35
Color range                              : Limited
Color primaries                          : BT.709
Transfer characteristics                 : xvYCC
Matrix coefficients                      : BT.709
Codec configuration box                  : avcC

Dropped it to time line in VP15, matched project settings with file settings and in Best | Full got 25fps on preview (8-bit pixel format, 32-bit pixel format -- 9 fps. file on SSD).

CPU utilisation was 54%, GPU - 17%. PC info in signature (it is not high end PC).

Hi Fifonik,

Ill try the same.What GPU is it ? Addon Graphics card or processor inbuilt graphics only ?

It is discrete GPU, Ryzen 1600 does not have integrated GPU (you could easily google this)

If i wanted to upgrade for better performance. Which processor of these 2 would you recommend, Core i7 8700k or Core i9 9900k ? Which of these 2 would be a better option to use Sony Vegas on ?

Im working with 720p proxy files only. Even that im not able to playback in anything above Draft Half. For 720p proxy shouldn't even my i3 6600 be enough to playback at least at DRAFT FULL setting.

# MY CURRENT SYSTEM :

Processor - Intel Core i3 - 6100 (6th Gen) @ 3.7 Ghz. 3 MB Cache. Socket - LGA-1151, With Inbuilt Intel HD530 graphics (3 Monitor Support), DDR4 Compatible.
Motherboard - Gigabyte, GA-B250M-DS3H, LGA-1151, Motherboard, 3 Monitor Support, HDMI+DVI-D+VGA Ports.
Graphics Card - No. Using processor IGPU Intel HD530.
Ram - 2x Kingston HyperX FURY Ram, Black, 8 GB, DDR4, 2400mhz, CL15 (Model -HX424C15FB28).
Primary HDD - Kingston SSD (SUV400S37120G).
Footage Drive - Seagate 2TB (ST2000DM001) 7200rpm.
Render Drive - Seagate 500GB (ST3500418AS) 7200rpm.
Backup Drive 1 - Seagate 2TB (ST2000DM001) 7200rpm.
Backup Drive 2 - Seagate 500GB (ST500DM002) 7200rpm.

Im willing to invest in a better processor as mentioned above (both are LGA1151 and suit my current board) but ill be stumped if i buy that processor and then i get the same crap DRAFT HALF struggling to render and crashes during color correction of video stabilization etc. And then someone says, its not the processor, you should rather have upgraded to a good video card LOL.

PS : Haven't bothered with a video card because i never ever play video games and i heard the graphics card doesn't contribute squat to Vegas timeline playback and towards renders either.

Of the 2, obviously the i9 9900k since it has additional cores. I have the i7 8700k and it works OK for my needs. You should probably add a dedicated video card since the Intel graphics is pretty limited. Whoever said this "i heard the graphics card doesn't contribute squat to Vegas timeline playback and towards renders either" is dead wrong. It is extremely important. OTOH, the Intel GPU may be OK for your purposes. Regardless, first upgrade your CPU (which is most important IMHO) and if the video performance is still below par, then upgrade the graphics. If $ is limited, I'd go with the i7 8700k and add a graphics card such as an AMD RX580 or comparable Nvidia card. You should also consider adding additional memory to at least 16GB. Just my nickel's worth.