Moving Database Cluster to another drive

Hi all, first some context.

I've had a tread about this topic on pgsql-general(at)postgresql(dot)org mailing
list (Restarting DB after moving to another drive). I had a lot of help to
learn how these things should be done from pgsql general list. However, at
this point, I feel I should continue the tread on the novice list because my
questions are getting more basic about PostgreSQL and databases.

I have a large PostgreSQL database (2TB) on my PC (Windows). Few weeks ago,
the drive dedicated to pgsql started overheating and I decided to move the
DB on a new drive. Considering my particular context and the time it was
going to take to restore from pg_dumpall output, I decided to copy the
content of the old drive to the new one and make things transparent to
PostgreSQL - if possible.

As expected, I was able to copy the database cluster on the new drive during
the night. I changed the drive letter to fit the original database drive and
I restarted the DB. Since then, everything seems running on the new drive as
it used to be with the old one, with a small exception...

The time expected to run queries on some tables seems longer. My questions
are .

- How indexes are actually implemented in PostgreSQL (how pgsql point to a
record from an index)?

- Could copying tables and indexes have had an effect on indexes?

- How can I verify that some of the indexes were not corrupted?

Daniel