I had a new hard drive installed. Wonderful Seti@home rainbow screen saver not operating. Think all preferences are in place. Please advise in SIMPLE terms how I can restore my screen saver. Thank you.

On the account you post with you don't have an active BOINC installed. So if you haven't yet, start there.
https://boinc.berkeley.edu/download.php
Use the version without VirtualBox, it's not needed here.

Meanwhilst, on the project preferences page make sure that SETI@home v8 is selected. Make sure that Use CPU is selected.

When BOINC is downloaded, install it and make sure that in the third screen in the installer, you click Advanced.
Check in the next screen that "Use BOINC screensaver" is checked. Continue the installation.
Start BOINC Manager (Start->Programs->BOINC->BOINC Manager)
The add project wizard should start automatically, but if it doesn't, do Tools->Add project; select Seti from the list; check "Yes, returning user" as option; fill in your email address and password for the account you're posting with->OK.

If you have a GPU (AMD, Nvidia or Intel), it can be used to calculate tasks. These tasks however do NOT use the screen saver/graphics. So tasks on the GPU do not use the screen saver or graphics. Repeating that.

Only tasks that run on the CPU only have the screen saver/graphics.

But the above should do it.

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