Not enough space on runtime

If you added an unsupported CPU then sure you'll get that error; often related to a TDP rated (CPU TDP > MOBO TDP supported) overage <or> CPU is 'unsupported' by current BIOS version, lacks CPID, solution is to update the BIOS.

Q - What MOBO?
Q - What CPU?

Chances are the CPU is not on the Supported CPU List or BIOS is out of date. ;)

There are other 'Not enough space on runtime' - some are 'ROM' related. For this section I assume 'SMBIOS' variety.