Our PC and Excel configurations

Our primary PC configuration

i7 Intel processor (we do have some with i5; we don’t notice a significant difference).
Windows 7 with Classic Shell. Classic Shell lets us set up our PC with the classic XP start button and menu which we love.
Trend Micro Anti-Virus and MalwareBytes Anti-Malware. Trend Micro seems the best on speed if you open and close a lot of files. And both have been top rated over the years.
240 GB Samsung SSD Pro drive. We keep both our system files and documents on it.
One internal 4TB hard drive for image backups.
One internal 1TB hard drive for incremental daily backups.
Dell 24" 16:10 U2412 anti-glare non-touch screen monitors. We use 16:10 as that gives more real estate than 16:9 monitors.
Ergonomic keyboards. A bit difficult to learn to use at first, but well worth it.

Our main machines are not allowed to be written to by other PCs. This is to prevent virus infections from other PCs.
Portable USB use is at an absolute minimum. No visitor USBs are allowed to be brought in and plugged into our main PCs. We have a special machine for such.
We use a sandboxed web browser for web browsing.
- Browsing in a sandbox is one of the best ways to prevent drive-by virus infections.
- For information on what this means and the program we use go to www.sandboxie.com.
We do a full virus scan daily on a scheduled basis.
We backup religiously. See our backup approach.
We have found that Excel 2013–2021 and Excel for Office 365 is a perfect match for a machine with multiple monitors.
On machines with just one monitor we strongly prefer Excel 2010. Trying to view two files at the same time in 2013 and above on a single monitor is too painful to imagine.