None of the two solutions works for me!? I have Excel 2013 - is that the problem?
Try this ...
Step1 - Create a named formula
Select cell A1 (this is important!!!)
Formulas > Name Manager > New
Name: IsFormula
Refers to: =GET.CELL(48,A1)
OK
Step2 - Apply the formatting
Select the cell(s) you want to format.
Home > Conditional Formatting > Manage Rules > New Rule
Select "Use a formula to determine which cells to format"
Enter this formula in the text box "Format values where this formula is true:
=IsFormula
Click the Format button
Select the desired style(s)
OK