I noticed this just recently. I specifically check my hard drive usage from time to time. I have a 1TB hard drive and I'm at a point where I have to make compromises if I want to install a new game or what have you with only about 350 GB left. Anyhow I thought I noticed that my space had gone down in the very short time I had just checked it. So I went ahead and uninstalled another game and immediately looked at what I had. As of yesterday I had 350GB of free space left. Today I check and its down to 347. I can understand that maybe windows updates might be installing when I don't know it or even a game on Steam maybe happens to be updated but this is not the case between last night and today. I can't understand however how does as much as 3GB just randomly disappear?

Again, I've not had any Steam games have any crazy large updates and I did not recognize Windows update doing anything within the past couple of days. What could be going on? Unfortunately I've had a couple of odd computer issues this week out of the blue. I rarely ever, ever get a BSOD. In all my years of pc usage and gaming I may get one once in a blue moon but it usually doesn't happen again for years. Earlier this year I had one. However this week I had two! I can't figure out what is doing that. Windows can't even really do a proper startup repair as it just seems to hang. I've also been trying to figure out another pc issue I've had but in recent months has become thankfully seemingly as though its clearing up. Basically when I would start my pc for the day, everything looked and worked find on the desktop and what have you. However when I would go launch a game like Witcher 3 or MGSV, it was as though my games were playing at a locked 20fps. No matter what game I would try, it ran in slow motion so to speak, very poorly. I think after months of trying to figure out what's doing it, I've noticed that in the resource monitor that my memory usage kind of becomes backward. Where normally(if I'm not mistaken that is)your memory should show a majority of the bar as light blue(free) it shows half or more as dark blue(standby). Even right now I notice that in task manager its doing this today. To "fix" it I usually end up having to shutdown my computer, wait a moment, then restart and usually(not always) after the computer starts and the desktop loads in and settles, when I go to check the resource monitor the memory has freed up and the bar returns to mostly light blue, free memory. I also notice that my hard drive always tends to have what look like really hard and long spikes. Now I don't know much about these things. I'm not too tech savvy but could there be an issue with the hard drive or memory or both?

I'm pretty good about cleaning my pc. Last year when I was having real problems I re-seated some components and the liquid cooler on the cpu. I didn't know until later that its super important to make sure that if you do take that off that its recommended to reapply thermal paste. I did not. I carefully returned it back together and there was still some paste on on it. I haven't had any overheating issues that I know of but should I also re-seat the cpu cooler again with a new application of thermal paste? I had bought some back when I was having all the issues happening at their worst last year but for the most part this year, all the problems went away save for what has just started happening with the BSODs.

Sorry for dragging on but I felt it important to list a couple of the other issues I've run into. Maybe it has nothing to do with my original question but I can't understand how a whole 3GB disappears over night.

It's your pr0n downloads

When was the last time you've wiped your PC? Might be time for a new, fresh install. Drastic, I know, but it's gotten to the point now that I view it akin to spring cleaning, going through the house to clear out all the old junk.

Did this happen after you've fiddled with some component inside the PC? This is how my Task Manager looks like...

Check that you aren't using that "Restore point" feature or what's it's name. System Management - Advanced Properties.

Scandisk for finding possible errors in the file structure.

Could also be a browser not deleting streaming videos or other temp junk like that.

Run these if you don't already...

Ccleaner https://www.piriform.com/ccleaner/download

ADW Cleaner https://www.malwarebytes.com/adwcleaner/

Malwarebytes https://www.malwarebytes.com

Run disk clean-up (chose scan for system files). You may well recover many gigs worth of space,especially after certain Windows updates.

I appreciate the advice, however I don't think the missing hard drive space is a problem. Something else is going on. My GBs have been the same for the past couple of days however when I mentioned I've had a BSOD twice in two weeks, I have had two BSODs today!!! I don't know what's going on. I usually never have things like this happen. I don't know how to associate what might be causing it. I seem to find that when I turn my pc on for the first time in a day, that periodically it does that thing where every game runs in slow-mo. I have gotten into the habit of after turning my computer on for the day, I shut the computer down for a few moments and then restart the computer. Then it seems to run fine the rest of the day. However today I have had two BSODs, one while starting up a game and another later today when I was watching a video on Youtube. Really kind of unsettling as it does not give you any warning that it going to happen, all of a sudden the image freezes then you get a slight buzzing sound while the BSOD comes up and then dumps a page of whatever and shuts down.

I run disk cleanup compulsively almost every day and multiples of times. I checked to see if I needed to do a disk defragment because I've not done one in a long time but the anaylzer said it was 0% fragmented so I didn't do one. Though I'm not actively looking for it, I don't notice any indications of over heating. My memory readout is usually always in the light blue(free space)segment of the memory bar and then sometime goes and flips to where standby(dark blue) fill up half the bar and the free space goes down. I've read where people say having a lot of standby percentage showing is a good thing but sometimes I think that may be when the pc and games specifically start to do that slo-mo thing almost as though memory is not being freed up. I ran a SFC /Scannow with no errors. Do you think it could be a memory thing or something else? Maybe I should reseat my memory stick and reapply some thermal paste?

Chucky I installed Malwarebytes. It detect some potential unwanted programs or threats. Nothing was labeled as virus but it came up with 8 "pups" and they looked like things in the registry. I let them put it in quarantine and restart my computer. I've always been a little confused with these programs. Is the way to delete and permanently remove the threats to empty the quarantine? Adwarecleaner got some pups too I think but all it does is restart the pc to finish. I've run AVG recently and there were no threats nor any popup warnings.

Once they are in quarantine they are made 'safe' as far as I am aware but you can manually delete them also if you wish. Yes,ADW forces a restart if it finds anything to complete the clean-up and gives you a report on start-up.

The BSOD,well I think that may be something else not related to the pups you removed. Other than try to make sense of any error report the BSOD gives you I think you have a mission on your hands but temps would be a good place to start.

I would remove and clean the memory contacts. My sister's PC started running really slow recently. I knew it had 4GB of ram but it only showed 2 when I went to inspect it. I suspected a duff ram module so removed and cleaned everything. After swapping other modules I had spare into it to see if the slots were ok I re-fitted the original pair and bingo,the 4gb showed up and it's been fine so far.

Maybe also check the health of the drive,I'm sure there is software out there for free that will do it.

What about a clean O/S install? I know it can be a pain,that's why I have all my games/data on a separate drive so it makes it easier.

Agree. I do the same (OS and easily re-installed applications on C: drive -- games, file saves, system image on different drive or drives). Its worth considering.

In particular, I worked out that I could (and did) spend more hours trying to fix a problem (and still not fix it) than it took to reinstall OS and easily installed applications (e.g. LibreOffice, Blender).

Also, once I reinstall, I make a "System Image" -- that I update every month or two (saved on the second drive). My first choice is to use the last System Image (very quick/easy to do). However, if it doesn't solve things, I clean install.

For what its worth.

Well thank you all for the tips. Its much appreciated. Is there a log somewhere stored when a BSOD happens? Obviously I can't get a screen capture of the event and the message doesn't stay up long enough for me to be able to read it as it happens fast.

Right click on the "This PC" icon and choose "Properties"
Choose "Advanced system settings" click the "Setting" button next to "Start-up and Recovery"
Untick "Automatically restart"
Click "OK"

Now when you get a BSOD it will stay on the screen until you press the power button.

Edit, "This PC" in Win 10 = "My Computer" on Win 7. Everything else should be the same.

Hmm interesting Mark A. Thanks for that. Speaking of the BSOD, what is that unsettling buzz that accompanies it? Also, When my trial version of Malwarebytes ends, does it stop working altogether or does it revert to some sort of limited free version?

It reverts to the 'free' version.So no real-time monitoring.

Not sure on the buzz but I think graphics cards can emit such a noise.

the buzz if coming from your speakers, occurs because the system has frozen up hard and the last several bytes loaded in memory are being played through the speakers.

missing hard drive space is often caused by some program downloading updates in the background. windows 10 is very notorious for this.

other candidates are sims like DCS which don't auto update but when you run them, they may download several gb at a time in an update.

other possibilities are system restore points and temporary internet files.

check your recycle bin to see if it's getting full of files - even if they're in the bin they take up space, so empty if out if you don't need the files in there anymore.

press ctrl+alt+del and then use the "performance monitor" button. click the "disk access" tab in the perf. mon. tool and see what process or service has the highest "total read/write" footprint. that will probably be your culprit. just make sure to look at it over the long term, not short term. leave the perf mon up while you use the pc for a few hours and see which program is using up all that disk.

Okay thank you all very much. You've been very helpful. After a day or so I went ahead and deleted what Malwarebytes put in quarantine. I seem to have had two good days with no BSODs. I hope a regiment of Malwarebytes and Adware cleaner and observing my resource monitor will help my PC to fix itself from whatever that problem is.