Lagging after Import

I'm completing some of the BM Resolve tutorials and running into a performance issue. Every time I import a project or a new timeline Resolve starts lagging badly. This happens regardless of whether it's been open for ten minutes or an hour. Closing and restarting Resolve (without rebooting) solves the problem. Then it runs perfectly, until I import another timeline or project, at which point it lags until I restart again. The lagging also occurs if I create a new project and import media. Same cure - restart Resolve and I can work problem-free until I use the import function again.

I can't remember when this started. At least a few weeks ago, maybe even with the 19.4 update. I'm using v19.4 (Studio) with latest WIN 11, a water-cooled i9-1400k CPU, an Nvidia 4090 GPU, 64 gigs of DDR5, 2 internal NvME drives and a fast external SSD. Plenty of space on all drives. Clearing Render Cache has no effect. I've checked resource use while lagging is occuring. No resource (memory, CPU, GPU) is over 25% and I have plenty of empty space on all my drives.

Let me stress that Resolve ONLY lags (badly) after I've used the Import Function and it lags EVERY TIME after I use the import function, so I'm pretty sure the problem is somehow related to that function.

Restarting Resolve takes under 1/2 minute, so it's no big deal, but it is rather annoying. Any thoughts?

What happens when you take the external drive out of the equation?

Hadn't tried that but, it changed nothing. Ditto for moving my cache files from the media drive to the system drive, a suggestion I got in a Facebook group. Still, thanks for the suggestion.

OK.

Some very generic things to check would be:

1. No VPN
2. All displays connected to the 4090. (Or a Decklink. Just...not the mobo.)
3. No third-party security. (Use Windows Security only).

Okay to all three.

Alright.

This is definitely not normal. In the years I've been posting, I can't recall anyone ever reporting this. My only guess is some weird system issue.

Is this a dedicated edit system? Nothing installed but what you need for the job? (No games, no email, no office, no development, etc.)

Nothing is overclocked?

No, not normal, which is why I posted it. Yes, there's lots of other software installed. As a hobbyist, I'm not in a good position to dedicate a $4k machine to one program. And yes, it's running a small factory overclock. Both of these things have been true since I got the machine 18 months ago but the problem is only a couple of months old, so I' was pretty sure that neither of your suggestions was on-target but, guess what? I turned off the overclock, imported a project and a bunch of media and it worked just fine. Go figure. Thank you so much for your help.

Overclocking is not recommended when using Resolve.

I turned off the overclock, imported a project and a bunch of media and it worked just fine.

Well, alright!

That makes no sense.

First of all K chips are unlocked. They run at whatever speed your cooling can manage. If you aren't overheating you aren't "over" clocked. These aren't locked speed chips.

I've no good ideas. My guess is there is a Windows issue or something.

They run at whatever speed your cooling can manage.

I've never heard that before. Cursory research suggests that K only means the user CAN increase the clock speed (or not), not that the CPU will do it on it's own. (Not counting turbo mode here.)