ISBoxer-issues

Hi guys!

Sorry for the wall, but I'm in need for some input here.

I've been a ISBoxer-user for all my multiboxing adventures so far. I've invested a lot of time into learning it, and have made rather advanced setups that I've enjoyed playing with.

However...

Recently, for no reason I can find, multiboxing with ISBoxer causes these intermittent, yet infuriating, FPS-drops / freezes. They last a second at most, but as many of you may know, this could be detremental.
At first I thought nothing of it, as I was idling in Dalaran/Orgrimmar, etc., and figured it would get better once in a dungeon or raid. No such luck, I'm afraid.

I've disabled all (except ISBoxer) addons
I've tried reducing graphics and resolution drastically
I've tried looking into core usage, thinking the CPU-profile was bonkers
I've looked into the cores themselves, thinking some may be parked for some reason
I've tried going away from the VFX-setup I've been using in ISBoxer
I've tried starting with a clean ISBoxer-profile, thinking there were a bit too much stuff being loaded
EDIT: I've tried monitoring the load on GPU/CPU/Memory, including the temperatures, but found nothing of note there.

Nothing stops the damn freezes.

Funny thing is; when using HotkeyNet, I can run all five, with improved graphics, with no problems at all.

I run 5 at a time, but I've been to Naxx a couple of times, running 10 clients on one (this) PC. I did notice some trouble there when **** hit the fan, but nothing compared to what I am seeing now with ISBoxer.

What gives?

I know my graphics card is severly outdated, but it has been working fine for as long as I can remember.

I am running the following:

GTX 970
Ryzen9 3900x
32gb 3600Mhz RAM

As noted, I've tried reducing from 1440 to 1080, and even further down.

One positive thing about this is learning HotkeyNet, which I've been curious about for a while. I'd prefer sticking to ISBoxer, but if it isn't possible on current specs, then...

Set fps strat for something like 60 foreground / 7 back @all chars, 60 / 12 for melee chars. Anyway, cpu related issue, not gpu one.

I did try playing around with that as well without seeing any difference, but not on those levels.
I'll give that a go.

Thanks!

One thing that comes to mind is play with one window at a time, make windows layout 1 fullscreen and the rest hidden behind it, maybe you will see improvements. I keep my windows at 30/10 fps limited and play with 1 screen, I cannot see what my other boxes are doing and it helps with my performance.

Cheers.
I did give that a go, actually. That is my standard layout, so it was basically just me disabling the VFX setup I had going. No improvement, though.

Not that I found the root cause, but I did get a 1070-card on the cheap and have had no issues since. No other changes done except that.

So back in business now :)

Thanks for your input!