Malware, Reset PC, Sudden Major Sluggish Speeds

Here's a story...a few days ago I got hit with malware. Someone got ahold of my PayPal information and tried to buy some things. I'm getting those taken care of.

Meanwhile...back in Windows 10 version 1803 (installed on a 120gb SSD, data installed on 1tb HDD)

After running Avast scans multiple times to find all the malware it could, everything seemed OK. Then I noticed some serious skipping in songs, and sometimes I would get an error somewhere along the lines of "the audio driver crashed." I also had some serious lag in programs and some would frequently become unresponsive. Thinking it could be fixed with a nice "Reset PC," I bit the bullet and enjoyed every minute of trying to reinstall everything.

Now, everything is inexplicably sluggish again. Especially when doing things related to my HDD. Things were absolutely fine one day, then the next was like someone jumped in my computer and installed an invisible bottleneck. Programs becoming unresponsive again...even ending a task would lag.

Could this be related to my malware? I have every driver installed/updated. Think a good ol' complete format and reinstall be in order? Although, I'm thinking that wouldn't fix the HDD lag. It's fairly fragmented but nothing Windows couldn't handle in the past.

Oh, and one last kicker: I spilled a cup of water into my PC maybe a month ago. Rejoice for the top mounted fans! Could everything be starting to kick into serious hardware failures? Things were running fine for quite a while after my failed water cooling attempt (humor!) so things going from good to bad really quick makes me think it's not hardware...but then again. Water.

Here's a first step:

Take a look in Task Manager when it's sluggish.

Look at the Processes tab.

What is using up the most CPU, Memory, and Disk when you sort by those columns?

What items show as "enabled" in the startup tab?

Well, I guess I should give my background: I'm a 25+ year PC veteran, so I've checked all the usual things. Nothing even gets near 25% of max. SSD test says it's good health, HDD test is good health. I've been running Defraggler overnight and the HDD is low on fragmentation, which I know these days does't really mean much.

The only thing I haven't had experience with is that level of malware infection, and the water accidentally spilling into my PC.

I was thinking of getting a big enough USB drive to format my SSD and reinstall Windows. I keep forgetting if the activation for Windows 10 is on my Microsoft account or not. I got the free upgrade from 7 > 10, so I have no CD key or whatever I had years ago.

Porthos said:

You can clean install any time and as many times as you want. Once you get online again it will auto activate for you.

Excellent. My plan is coming together perfectly. Except for my PC being screwed up part.

Good news! Reinstalled Windows from a USB drive, formatted SSD, copied important stuff from HDD and formatted that. Everything is back to normal.

Still sluggish....because my computer is ancient. FX-8320. Six years old. Yuck. Anyway, thanks for the tips, guys!