Removed the quotation marks to fix second and third values for $VAR1. Just need to figure out the first result now, note the two leading spaces are intentional below, this is how it appears in the output

#!/usr/local/bin/perl
##
use strict;
use warnings;
use Data::Dumper;
my @output = (
     qq/Hardware\n/
    .qq/   cisco Nexus 3048 Chassis ("48x1GE + 4x10G Supervisor)\n/
    .qq/   Intel(R) Celeron(R) CPU P450 with 3981680 kB of memory.\n/
    ,
     qq/Cisco CISCO2901\/K9 (revision 1.0) with 483328K\/40960K bytes 
+of memory.\n/
    ,
     qq/cisco WS-C3550-48 (PowerPC) processor (revision N0) with 65526
+K\/8192K bytes of memory.\n/
    .qq/Model number: WS-C3550-48-SMI\n/
);
print "@output\n";
foreach (@output) {
    my %details;
    if (/^Hardware/i) {
        $details{'Chassis'}     = $1 if (/^cisco Nexus (\S+)/i);
        $details{'Main Memory'} = $1 if (/^Intel (\S+)/i);
    }

    if (/^cisco ((Catalyst )?\S+) .* with (\S+) bytes of memory/i) {
        $details{'Chassis'}     = $1;
        $details{'Main Memory'} = $3;
    }

    $details{'Chassis'} = $1 if (/^Model number: (\S+)/i);
    print Dumper(\%details);
}
[download]

Result...

Hardware
   cisco Nexus 3048 Chassis ("48x1GE + 4x10G Supervisor)
   Intel(R) Celeron(R) CPU P450 with 3981680 kB of memory.
 Cisco CISCO2901/K9 (revision 1.0) with 483328K/40960K bytes of memory
+.
 cisco WS-C3550-48 (PowerPC) processor (revision N0) with 65526K/8192K
+ bytes of memory.
Model number: WS-C3550-48-SMI

$VAR1 = {};
$VAR1 = {
          'Main Memory' => '483328K/40960K',
          'Chassis' => 'CISCO2901/K9'
        };
$VAR1 = {
          'Main Memory' => '65526K/8192K',
          'Chassis' => 'WS-C3550-48'
        };
[download]