You can also use a negated character class to match everything except what you don't want 
my ($match) = 'wppwd01a0099_NET_basp_virtual_adapter' =~ /^([^_]*)/;
print $match;

#wppwd01a0099

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In reply to Re: minimal match regulara expression by trippledubs
in thread minimal match regulara expression by fionbarr

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