Your problem may be from system("clear");

But anyway, to create a question menu, I truly recommend the Term::UI module:

use Term::UI;

my $term = Term::ReadLine->new('brand');
my @pc = qw(comp1 comp2 comp3 comp4 comp5);

my $reply = $term->get_reply(
                             prompt  => 'Which computer would you like
+ to cold start? ',
                             choices => \@pc,
                             default => 'none',
                            );
[download]