Confirmed my CPU supports QSV. Use hardware acceleration is ENABLED. Plex is running as a service.
No transcoding is taking place.
Since my CPU QSV version does NOT support HEVC decode/encoding.
Why doesn’t Plex transcode using QSV when it transcodes HEVC -> h264?
Does the hardware acceleration in Plex only work if it can decode and encode the original format and new format?
If my QSV CPU supports h264 hardware encoding, shouldn’t it then be used when transcoding?
Seems silly to require support for both original and transcoded codec for HW accel. Even if HEVC decoding isn’t supported by CPU QSV, the CPU usage will be fairly low thus still a net gain with HW encoding.
Plex can use hardware encoding even when doing software decoding.
Plex-as-a-service cannot handle hardware encoding or decoding. To use hardware acceleration, Windows requires the software to be run from a logged-in user. It’s not a Plex limitation, it’s Windows.
You have two choices:
Run Plex as a logged in user (I create a dummy account that auto-logs in just for Plex).
Move to Linux. It works fine there as a service with acceleration.
Thank you for the clarification. I had tried adding Plex as a service cause I read somewhere that transcoding issues could be resolve that way.
Since using linux is not an option at this time I will be going with option 1 you listed. The system that is running Plex is always on and autologons in and runs Plex and has been running that way since installation. HW transcoding was not working then as I tried it before doing the Plex as a service thing.
To summarize, Plex originally ran under a user account that is in use 24/7, but idle. Is this the what you mean in option 1 or is it some other method?
Edit:
FWIW, I tried just using ffmpeg on its own on that system using h264_qsv and works perfectly for encoding. Plex, no dice.
You’re correct (I believe!). For option 1, I set up my system so that there’s a separate login just for Plex. That way I’m not using my Microsoft account and setting it to auto-login. It also gives me the ability to limit permissions as I wish.
I have Plex installed on that account, so that when it logs in, it automatically loads Plex (and you can see it loaded in the taskbar as well). When doing that, it uses hardware acceleration fine. Well, mostly fine, I’ve found Windows support for QSV to have some spottiness, to be frank.
Plex should be able to use hardware acceleration for most encoding, and for some decoding (at the minimum, h264/AVC should be decoding in hardware).
One additional note: For some users, Windows needs to have an active monitor plugged into the video card. For other users? It works just fine. I’m not sure if this is related to some recent update in Windows. Just FYI, in case you’re looking for a way to tinker with it when seeing problems.
I didn’t realize you could have multiple accounts login simultaneously and run programs on startup in the separate accounts. Is there a walkthrough somewhere on how to do that?
I agree that it should and ffmpeg confirms that it’s enabled/available but it isn’t.
There is a monitor connected to that system. Also, it’s Win7 if that makes any difference in your experience.
Unfortunately this would be a deal breaker for the Plex Pass if I can’t get it working.
You know what, that’s a good question about the multiple user accounts. To be honest, I can’t remember the rules for whether you can have two active logged in users in Windows 7. I’ve been using RDPWrap for desktop OS’s, which allows you to log in with two accounts at once via remote desktop.
I think you can set up multiple user accounts with fast user switching, but I’m not 100% sure. Check this out.
It’s possible you’d have to use a single account, and can’t use a dummy account. If so, I just didn’t think that through for your situation, which is my fault. I’m a bit out of practice on Windows scenarios outside of my own.
First, OS has no bearing on what CPU people use. However yes my CPU in older that 6th gen.
Second, as discussed above, I need HW ENcoding, not DEcoding. User Cafe_Diem says that Plex should be able to SW decode HEVC then HW encode to H264. Are you saying this is incorrect and Plex does not have this capability?
So Plex requires that for HW acceleration, the device must support the original and new codec for decoding and encoding? Please clarify.
If it fails the Hardware Decode test, Plex then drops to software for Decoding/Encoding. Same reason why you can’t put multiple GPU’s in, it only tries once.
Absolutely not. Plex will still encode in hardware even if decoding falls back to software. I’m not sure why you’re being told otherwise. Here’s a screenshot I just took with software fallback for decode (My hardware can’t accelerate HEVC 10-bit), and hardware acceleration for encode.
Well, I agree with you there. My concern also with this transcoding issue, is that there is exactly ZERO support from Plex. While your help and everyone elses is appreciated, an official response would be helpful.
Ultimately I’d rather have it working and NOT refund but it just doesn’t work and getting conflicting answers.
Ditto, it would be great to just get this working for you. On a lark, I just did a transcode of VC1, which no hardware can accelerate in Plex (as far as I know!). Take a look.
Plex can absolutely accelerate encodes even if decode acceleration is unavailable. If you’re logged into your machine, have Plex installed, are logged into your Plex Pass account, and you’re still getting no acceleration, that’s really strange. What CPU are you using? Do you have any other video card in the computer?
This might be time for logs. You can go to the troubleshooting section of the Plex settings, and there is an option there to download your logs. (BTW, there is also a section there for “Console”. You can watch your logs live as you try to play something, which can be really handy sometimes).
I’m honestly not sure where the problem is happening. Hardware acceleration problems can be weird.
I’m heading out for a while, it’s possible someone else could look at logs later. Also, if you look through the logs specifically named “Plex Media Server”, you can go to the time stamps when you played something, and watch for any errors. You can then search for errors here on the forums. To be honest, it’s often what many of us do.
A quick note: You can typically leave verbose debugging turned off, debug should be good enough in most cases and it’s less for you to dig through.
I did some digging through the forums, and found this with no replies:
So, you’re definitely not the first one to run into this. I’m not exactly sure what the solution is, or even if there’s a solution. I don’t have any Sandy Bridge hardware to bring online and test with. So I might be stalled in terms of ways to help you here. I’m kind of hoping another forum member has gone through this with this chipset. (Is there anyone out there? Hello?)
Semi-related topic: To my understanding, hardware encode acceleration is significantly below-average with the Sandy Bridge era, and doesn’t really pick up until the 5th-gen CPU’s, where Intel began taking video quality a little more seriously. It’ll still be ok, just not great, and will need a higher bit rate to reach a decent quality. I know that doesn’t help you in this particular case, but it seemed useful to set that expectation up front if the problems can be worked out.
Hmm, okay. I’ll keep this open and monitoring for anyone that may be able to assist.
Ya know, I’m not looking for incredible performance out of it. I know it’s old but any little bit would help. Since the PC is used for other things, relieving the CPU of unnecessary cycles would be ideal.
Thank you very much for assisting as you have. It is appreciated.
If you’re willing to spend a small amount of money, and have a PCI Express slot in your computer, there are some fairly inexpensive Nvidia cards (under 40 bucks?) that could handle up to HEVC 8-bit decode as well as H264 encode at a max of 2 sessions. Just a thought if you’re considering options.
I’m also going to ping @anon18523487 here, maybe for a quick browse of this topic and perhaps some quick input on this issue. (Sorry to bother!)
