Maybe it is a requirement that item must be a key with its value a chip name, (Athlon 4000+). Instead, the chip name could be a key to an anon hash of the three other attributes, producing results with min. code.

#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;

my %chips;
{
    local $/ = "";

    while(<DATA>) {
        chomp;
        # Capture chip name in $1 and delete line with chip name
        s/^\[([^\]]+)\]\n// or die "error: ...";
        $chips{$1} = {split /[\n=]/};
    }
}

print Dumper \%chips;

__DATA__
[Athlon 4000+]
price=300 euro
produce=AMD
description=Fast

[Celeron 3000]
price=200 euro
produce=Intel
description=Slower
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