Hallo.
I bought a Dell Optiplex 7010 on Amazon. Used and reconditioned.

It came with a WIN10Pro on board, but I decided to erase it and install Linux because it was incredibly slow to startup and every time I launched an application for the first time, for some reason the PC froze for some minute with the drive at 100%.

So now I have formatted and installed Kubuntu 22.04.

BUT: I am experiencing similar problems. The start-up of the machine is very slow, but more than that, after startup the very first time I run Firefox, or Thunderbird, or Libreoffice, it takes 30sec. to 1 minute to open the window, with the disk working like mad.
Only the very first time, after that if I close Firefox and open it again it is instantaneous as it should be.

The thing that makes me post this into the Hardware forum is that the behaviour seemed to be similar with Linux AND Windows, so...

Has anybody ever experienced something similar?

The S.M.A.R.T. diagnostics of the disk are good...

Thanks. I need to decide if it's the case to return the PC or not

whats the system specs?cpu,ram,hd

The Dell Optiplex 7010 is quite old. Please give specs of your machine. Because Windows & Linux are working slow it looks like a hardware issue.
Possible reasons:

• System has no SSD for OS. Start from HDD slows down every contemporary OS.
• System cooling doesn't work properly. Are all fans rotating? Is system nearly dust-free?
• Thermal grease or thermal pad between CPU and its heatsink is dried-out and therefore it gives poor heat flow.
• Thermal grease or thermal pad between northbridge and its heatsink is dried-out and therefore it gives poor heat flow.
• [possibly] System has less RAM, e.g. 4 GiB only.

Due to warranty conditions, it might be impossible to return it after pre-installed Windwos has been deleted.

BIOS setting for HD controller may need to be changed to AHCI from legacy or raid.

If RAM is not installed in matched pairs in associated slots, performance can suffer up to nearly 50%..

Specs obtained by KDE system info

Operating System: Kubuntu 22.04
KDE Plasma Version: 5.24.6
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.3
Kernel Version: 5.15.0-52-generic (64-bit)
Graphics Platform: X11
Processors: 4 × Intel® Core™ i5-3470 CPU @ 3.20GHz
Memory: 15.5 GiB of RAM
Graphics Processor: Mesa Intel® HD Graphics 2500

The disk is SSD Valuetech 256Gb

The Fans seems fine

I don't know about the BIOS settings...

Post back a terminal readout of
also using go advanced button in reply box and pasting the inxi readout in code tags using the # mark on the advanced reply toolbar.

I know Ubuntu comes with that command. Kubuntu probably has it also. Also was md5sum check done on your Kubunutu iso download to check for a corrupted download.

Your KDE specs show you should not be running slow.

Well, actually, I reformatted everything and installed Debian 11 with KDE and....
the result is identical.

So my conclusion is that the hardware is faulty. It's not possible that 3 different OS have exactly the same problem....

So, I am just going to return the PC.

Thanks all the same

Don't know what to say. Did not know Amazon had a refurbished store. I recommended replacing drive that came with it and storing it. That way you can install and a brand new drive. Still getting problems, reinstall the windows drive and return for refund. My wife's Dell I bought from Discount Electronics is an Optiplex 780 w/dual core duo processor. That's really old. I promptly removed the Windows drive and installed a brand new drive and installed linuxmint. It is slow to start but otherwise no problems.

Your Optiplex may well have a hardware problem. Don't know much about Amazon Renewed. Anybody know where they refurbish stuff? I do not think a hardware problem would get past Discount Electronics.

I used to work at Dell in manufacturing and refurbishing. Large corporations buy thousands of identical computers at a time, Keep them for x number of years and exchange them for new with dell. Pretty much like the way companies deal w/fleets of cars. The used ones get bought up in lots by people like Discount Electronics. Maybe Amazon is playing that game now. Parts People concentrates more on laptops.

If you ever buy a used one from Dell refurbishing and have problems be sure to get it resolved in 30 days. They had a practice of having you try this and that until you were past the 30 day warranty. If you report you think you smell smoke from the computer that will get an immediate response to send it back.

A neighbor bought a brand new Dell, the mobo went bad in a few days. They sent a tech to replace it, but not with a new one.

Dell corporate support was excellent but consumer support was very poor.