Windows OS basic maint tasks can be adjusted, but depending on how granular you want to be, the tools/level of sophistication to pull that off is not small/insignificant. I'd argue it isn't worth the effort (knowing what that entails) to enable booting up PC 5-10 minutes before service on an under-powered system and pull off a clean livestream
If a PC is left off during the entire week, booted fairly shortly before the service, then what you are experiencing is something I'd consider expected/normal/reasonable.
We start our streaming PC currently about 90->120 minutes before the service starts (for historical reasons). For most of the last year, I'd bring the OBS streaming Tower PC home during the week (first to learn/work on system), then more recently simply to let recording of Sunday service to finish Cloud Sync, and to make sure all updates, etc are in place. Just last weekend, after construction (and then fixing the contractor screws ups) we finally got system in permanent position (monitors wall mounted in choir loft, streaming PC in sound closet, etc). So, streaming PC is not coming home anymore, and pre-service boot time will shrink significantly. So we will have to adjust process to deal with same/similar issue. Fortunately, our process of downloading that week's Service Bulletin, and then fixing it takes a little time (15+ minutes) and I have trainees learning the whole process (including software-based PTZ camera controls). And then there is using Facebook's Scheduled Live Video (so open URL so non-Facebook folks can watch as well), with a Scheduled Video requirement of starting streaming 10-20 minutes in advance of Go Live, and then allowing time for any tech troubleshooting.. all of which means the PC has plenty of time to settle down before service starts.
Consider - (unless you want unplanned interruptions as you are having now) you will need to schedule maintenance time for the PC:
- for Operating System updates, and regular maintenance
- For Anti-virus scans (I suspect this may be one of you issues?? Do you have a HDD, or SSD? Security scans with only a HDD is often performance inhibiting.. fortunately, this is also usually the easiest to schedule for another time). Updating older PCs with only a HDD to include booting off a SSD can make for huge performance gains (ymmv, depending on exact details)
- OBS, and other updates (hardware drivers, etc)
My recommendation
- have whomever shows up first before service be responsible for powering on the PC. At a bare minimum, I'd recommend 20-30 minutes in advance, and ideally a bit longer. This gives the OS times to do its thing, and settle down
- AND then set aside a dedicated time for OS patching and other, and then test streaming afterwards to make sure all is well before next service/stream (right after service might work for some groups, other might be mid/late week (after MS Patch Tuesday). Personally, in general I try to avoid patching on Patch Tuesday and wait a few days at least (and watching commentary/tech news to see if an issue to be concerned about)
This is all basic computer ops/maint, that the vast majority of people don't do/pay attention to. So if seems like overkill, I understand, BUT, something you will have to account for to avoid interruptions (either that or a much more powerful PC that won't slow down even when background tasks running).
oh, and be sure to go into WIn10's Update Settings and adjust "Change Active Hours" so patching (install and reboot) doesn't happen during service
Good luck