Why o' Why is my PC slow ?...

The modern PC all do this as they age go slower, and slower  and  cause #1 is: (That HDD are born to fail, and self heal, and to run slower as they age. That is there THING!) A new SSD is one cure.
This page below is not about the internet slow as seen here.
The below topics are to cover  PC slow, just the PC alone.
Besides the Captain Obvious cures, like a newer faster PC, more DDR memory 8GB is better, and a super fast SSD boot drive upgrade.

These word HDD means Hard disk drive and for sure the Windows boot drive
  1. The HDD or boot up Hard disk drive is too full, so erase/delete all  those unused videos of girls gone wild?  MP4 , MPG, etc. files. (do not forget to empty the recycle bin last)
  2. HDD is bad failing smart tests. ( also a bad hdd even not the boot drive will slow the PC down even BIOS P.O.S.T's  slow and or  boots are slow, this means test all HDD in the system.)
  3. Too little RAM (DDR) and is captain obvious, but not if you over filled it. (or the bad guys did, those bad nasty App.s)
  4. Memory too full. (in Task manager) Control + ALT + Del, all 3 keys at once , click memory, see if RAM is full and what application cause that?, and remove them or buy more RAM.
  5. The CPU is overloaded, see that too in Task Manager above,  see CPU load not near 10% but near or at 100% that is overloaded. (again find the offending application and remove it)
  6. The PC is overheating, all CPU and GPU that overheat slow down by DESIGN in the SILICON (logic) Called self preservation as heat kills electronics dead or a very short life. (and fans scream)
  7. If using a SSD do not allow it to go over 50% full or it will have a shorter life span. Buy them sized 2 times your need,  256GB is ok, but 1TB is best. (SSD= solid state drive)
  8. Rule #1 on all HDD made (a.k.a. Rust drives or spinners) is all go slower as they age, the cure is buy a new SSD. (HDD love to slow down as they age and is captain obvious again.
  9. Last is the OS is corrupted.  (be it malware , a Virus or rootkits or Trojans) clean the PC using AV scans per below steps.
  10. Other hardware failures cause this too, so  run PC diagnostics to find that, after #2 test of HDD first. (Dell the best maker has F12 diagnostics, ePSA, run that first)


W10 actions on #9 above (Microsoft's built in A/V is very good, I've used it for 5+  years now, and zero problems) I also only  use free Malwarebytes, to make it stronger , just that.
In the  MS,  Security pages, turn on auto scans. 1st, then do full scan now here. (A/V = Anti-Virus, MS = Microsoft)
Do quick then full, if wise. (in the start + run box type windows security)

If the above scan  fails to find any Virus etc.,  then try these: (online A/V tests !)
There are many but ESET wins my award.

Norton:

Trend:

If all else fails reload the OS FRESH, as directed in you OEM PCs users manual under chapter "RECOVERY"

#5 Elaborations:  CPU over loaded? (CPU or Memory)  First is MS Systems Internal  app.
I use this fabulous utility (autoruns64) from MS  to find things I do not want on my PC.  < a safe free and portable APP,  no install at all !!
Pure bliss this app is. (no cloud or MS store needed to run it)!!! I run that and defeat most auto running apps, like Adobe for sure. (vast bloat-ware gets you vast auto update startup software, I kill all I see)
My auto runs are , only Fences and MalwareBytes.
Nobody with 100 apps loaded and needed, and with 100 auto-update engines in the startup folders, ever, but they are not listening to me. (but I don't care that I just  nuke them out of there using the magical app above)

enjoy !

If all else fails,  there is this great man, ask him for help. The late and great Johnny Carson (RIP)


Sorry for my poor jokes, but that makes life fun.

Jargon , (nobody wants to say central processing unit or Microsoft corporation, hard disk drive or solid state drive,  endlessly.)

version 1.  12-12-2020  (only w10 supported by me, time to upgrade?) by  C.Obvious