Very Slow PC

My recommendation for this is to use a Solid State Drive (SSD) for your operating system and a secondary hard drive for storage.

You can also use msconfig and disable any startup items what might be chewing up resources. Also check your RAM and CPU and see what is running when it slows down.

Another thing that slows machines down is auto scan for anti-virus. I would also check this.

Will.

Logon as a different user.
Is it better? If so, possibly due to malware, as others have said.
When scanning for malware, disconnect from the internet if possible.
Strangely named programs shown in Task Manager are further clues

A SSD drive and more RAM .  Barring that, since you have run CCLEANER, what about Autoruns from Microsoft?

I agree - this is an old system now... slow by most standards.  If you've been keeping it up to date with the latest versions of everything - including windows patches, MOST things have just gotten more resource intensive, not less.  Upgrade the RAM to 8 GB and put an SSD in it... you'll find that breaths a LOT of life in an older system.  But ideally, replace it.

(Could it be something else, sure, but odds are nothing you do will recover all that much performance short of hardware upgrades)

I have a similar system at work.  I put in an SSD upped the RAM from 4 to 8 gb. And I reinstalled the OS (new bit drive). Also, you should slipstream the new install if you go that route. This prevents the system from becoming clogged before it even gets started.

There can be many reason for the slowdown of PC.
Virus,  Malware, Temp Files, Too many programs installed. Check for proper installation of hardware's and cables
If you have checked the above all the things then i suggest you to replace the hard drive and then check.
It happened with me also i received new desktop with faulty hard drive. I suspect hard drive issue.

maybe the fastest solution would be a factory restore + all updates in this case, since it looks like it has been running for years
this will remove all"leftovers" - and restore it to the original speed
http://www.dell.com/support/article/us/en/19/SLN117599/EN

What kind of defragmentation was used? Have you defragged also MFT?

As I said putting all updates on,  instead of slipstreaming, will slow down the PC.  You cam use the current windows install as your slipstream base and add all updates as well as customizations if you use something like NTLITE (ntlite.com) or 7customizer (I know this works worth NTLite, because I have tried it).

To All,

Thanks for all your suggestions.

I have been very sick since yesterday, have not been able to try anything.

I have AVG Virus Software; it finds things regularly & removes them.

Should I put Adaware, etc., wth AVG on the computer or?

Thanks

Thanks

Malwarebytes would be good.

Do the AdwareCleaner first.  It doesn't need installation, you can just run it.  That'll give you an idea if your computer is infected with bad stuff.

See http://www.bleepingcomputer.com/download/adwcleaner/

To All,

Thanks for all your suggestions.

I have been very sick since yesterday, have not been able to try anything.

I have AVG Virus Software; it finds things regularly & removes them.

Should I put Adaware, etc., wth AVG on the computer or?

Thanks

Thanks

AdAware helped a lot. The responsiveness is much better & it is NOT banging the hard drive.

Should I still do bleeping computer & malware bytes?

Thanks!

You need to do all!
it can even be  - after running all these - that your pc is still infected - but let's hope not

If AdwareCleaner finds malware it is a good indication that there is still more.

Which is why you follow up with TDSS Killer and MalwareBytes.  TDSS Killer looks for a specific type of virus while MalwareBytes is general purpose.

In general, I find that speeding up this model computer is fairly straight forward.  As I mentioned previously, take these steps and I guarantee that you will have a speedier PC:

1. Install a Solid State drive and only put windows on it (use your old drive as the data drive)

2. Install the maximum amount of RAM for the OS and the Hardware ([url="https://www.dell.com/downloads/global/products/optix/en/opti_755_techspecs.pdf

8gb for the 755[/url])"]

3. Install a slipstreamed (using something like NTLite) 64 bit version of the operating system

NEVER install anything else on the C drive.