Facet API: grouping indexed values into several drop-down facets I have an indexed field which contains values in such a form:

CPU: Intel Core i5
CPU: Intel Core i7
...
Memory: 4 GB
Memory: 8 GB
...
Video card type: Integrated
Video card type: Nvidia
...

I would like to display these as several drop-down lists, e.g:

Title: CPU  with values: Intel Core i5, Intel Core i7, ...
Title: Memory with values: 4 GB, 8 GB, ...
Title: Video card type  with values: Integrated, Nvidia, ...

Any suggestions would be welcome on how to implement this.
Thank you very much in advance.

Best regards,
Laszlo
If possible, I'd use a vocabulary for each of the facets ('dropdowns'). Add a term referenece field to your node for each of those as well. Then add these fields to your search index and add the facets for them.

E.g.,
Vocabulary:
CPU

Terms: 
Core i5
Core i7
...

Vocabulary:
Memory

Terms:
4 GB
8 GB
..