VOTING AND SUPPORT AGREEMENT

         This Voting and Support  Agreement  (this  "Agreement")  is dated as of
March 16, 2000, between Amherst Computer Products Southwest, LP, a Texas limited
partnership ("Amherst Southwest"), and James H. Long ("Long").

                                   BACKGROUND

       A.   Amherst Southwest and Allstar Systems, Inc., a Delaware  corporation
("Allstar"), are entering into an Asset Purchase Agreement concurrently herewith
(the "Asset Purchase Agreement"). Capitalized terms not otherwise defined herein
shall have the meanings assigned to them in the Asset Purchase Agreement.

       B.   Long is the owner of a majority of the  outstanding voting shares in
Allstar, and desires to enter into the agreements set forth herein.

       NOW, THEREFORE,  in consideration of the premises and the mutual promises
herein made, Amherst Southwest and Long agree as follows.

                                   AGREEMENTS

       1.   Representations and Warranties of Long. Long represents and warrants
to Amherst Southwest that the statements contained in this Section 1 are correct
and complete as of the date of this  Agreement  and will be correct and complete
as of the Closing  Date (as though made then and as though the Closing Date were
substituted for the date of this Agreement throughout this Section 1).

            (a)  Authorization. Long has full power and authority to execute and
deliver this Agreement and to perform his obligations hereunder.  This Agreement
constitutes  the valid and legally  binding  obligation of Long,  enforceable in
accordance  with its terms and  conditions  except  as such  enforcement  may be
limited  by  bankruptcy,  insolvency,  moratorium  and  similar  laws  affecting
creditors' rights generally and to general principles of equity.

            (b)  Noncontravention.  Neither the  execution  and the  delivery of
this  Agreement  by  Long,  nor  the  performance  by  Long  of his  obligations
hereunder,  will  (i)  violate  any  constitution,  statute,  regulation,  rule,
injunction,  judgment, order, decree, stipulation,  ruling, or other restriction
of any  government,  governmental  agency,  or court to which Long is subject or
(ii) conflict with, result in a breach of, constitute a default under, result in
the  acceleration  of, create in any party the right to  accelerate,  terminate,
modify, or cancel, or require any notice under any agreement,  contract,  lease,
license,  instrument, or other arrangement to which Long is a party, by which he
is bound or to which any of his assets is subject.

            (c) Majority  Status.  Long owns legally and beneficially a majority
of the issued  and  outstanding  shares of Allstar  having  voting  rights  (the
"Majority Shares").

       2.   Covenants of Long.

            (a)  Majority  Approval.  Long  agrees  to vote all of the  Majority
Shares  in  favor  of  the  Asset  Purchase   Agreement  and  the   transactions
contemplated  thereby,  subject to  termination of this Agreement as provided in
Section 3 below.

            (b) Exclusivity. From the date of this Agreement through the Closing
Date,  Long will not (1) solicit,  initiate,  or encourage the submission of any
proposal  or offer from any Person  relating to the  acquisition  of any capital
stock or other voting securities,  or any substantial  portion of the assets, of
Allstar or the CP Division or the El Paso IT Business (including any acquisition
structured as a merger, consolidation, or share exchange, but excluding from the
prohibitions of this subsection (1) any sale or other  disposition of the assets
of  Allstar's  Telecom  Division)  or  (2)  participate  in any  discussions  or
negotiations  regarding,  furnish any  information  with  respect to,  assist or
participate  in, or  facilitate in any other manner any effort or attempt by any
Person to do or seek any of the foregoing. Long will notify Amherst Southwest in
writing  on the next  Business  Day if any  Person  makes any  proposal,  offer,
inquiry, or contact with respect to any of the foregoing.

            (c)  Press Releases and Public  Announcements.  Long shall not issue
any press release or make any public announcement relating to the subject matter
of the Asset Purchase  Agreement  prior to the Closing without the prior written
approval of Amherst Southwest;  provided, however, that Long may make any public
disclosure  which,  in the  written  opinion of counsel to Long,  is required by
applicable   law  or  any   listing  or   trading   agreement   concerning   the
publicly-traded  securities  of Allstar (in which case Long will advise  Amherst
Southwest and provide  Amherst  Southwest with a copy of such opinion of counsel
prior to making the disclosure).

            (d)  General.  If any further  action is  necessary  or desirable to
carry out the  purposes of this  Agreement,  each of the parties  will take such
further action (including the execution and delivery of such further instruments
and documents) as the other party reasonably requests.

       3.   Termination.  This Agreement  shall terminate if and only if (a) the
Closing of the transactions  contemplated by the Asset Purchase  Agreement shall
have  occurred;  (b) the Asset  Purchase  Agreement is  terminated  prior to the
Closing in accordance with and pursuant to the terms thereof; or (c) the parties
enter into a written agreement to terminate it.

       4.   General Terms.

            (a)  No Third Party  Beneficiaries.  This Agreement shall not confer
any  rights  or  remedies  upon any  person  other  than the  parties  and their
respective successors and permitted assigns.

            (b)  Entire  Agreement.  This  Agreement  (including  the  documents
referred to herein)  constitutes  the entire  agreement  among the parties  with
respect to the subject matter hereof and  supersedes  any prior  understandings,
agreements,  or representations by or among the parties, written or oral, to the
extent they related in any way to the subject matter hereof.

            (c)  Successors and Assigns. This Agreement shall  be  binding  upon
and inure to the  benefit  of the  parties  named  herein  and their  respective
successors and permitted  assigns.  Long may not assign either this Agreement or
any of his rights, interests, or obligations hereunder without the prior written
approval of Amherst  Southwest.  Amherst  Southwest may assign any or all of its
rights and interests  hereunder to one or more of its Affiliates,  and designate
one or more of its  Affiliates to perform its  obligations  hereunder (in any or
all of which  cases  Amherst  Southwest  nonetheless  shall  remain  liable  and
responsible for the performance of all of its obligations hereunder).

            (d)  Counterparts.  This  Agreement  may be  executed in one or more
counterparts,  each of  which  shall  be  deemed  an  original  but all of which
together will constitute one and the same instrument.

            (e)  Notices.  All notices,  requests,  demands,  claims,  and other
communications hereunder will be in writing. Any notice, request, demand, claim,
or other  communication  hereunder  shall be deemed  duly given if (and then two
business days after) it is sent by registered or certified mail,  return receipt
requested, postage prepaid, and addressed to the intended recipient as set forth
below:

            If to Long:                  c/o Allstar Systems, Inc.
                                         6401 Southwest Freeway
                                         Houston, TX  77074
                                         Attention:  James H. Long

            If to Amherst Southwest:     Amherst Computer Products Southwest, LP
                                         c/o Amherst Technologies, L.L.C.
                                         10 Columbia Drive
                                         Amherst, NH  03031
                                         Attn:  Chief Financial Officer

Any Party may send any notice,  request,  demand,  claim, or other communication
hereunder  to the  intended  recipient at the address set forth above (using any
other means, including personal delivery,  expedited courier, messenger service,
telecopy,  ordinary  mail, or  electronic  mail),  but no such notice,  request,
demand,  claim, or other  communication  shall be deemed to have been duly given
unless and until it actually is received by the  intended  recipient.  Any Party
may change the address to which notices,  requests,  demands,  claims, and other
communications  hereunder are to be delivered by giving the other Parties notice
in the manner herein set forth.

            (f)  Governing Law.    This  Agreement  shall  be  governed  by  and
construed in  accordance  with  domestic  laws of the State of Delaware  without
giving effect to any choice or conflict of law provision or rule (whether of the
State of Delaware or any other jurisdiction) that would cause the application of
the laws of any jurisdiction other than the State of Delaware.

            (g)  Amendments  and Waivers.  No amendment of any provision of this
Agreement  shall be valid  unless  the same  shall be in  writing  and signed by
Amherst   Southwest   and  Long.   No  waiver  by  any  party  of  any  default,
misrepresentation,   or  breach  of  warranty  or  covenant  hereunder,  whether
intentional  or not,  shall be  deemed  to  extend  to any  prior or  subsequent
default,  misrepresentation,  or breach of  warranty or  covenant  hereunder  or
affect in any way any rights  arising by virtue of any prior or subsequent  such
occurrence.

            (h)  Severability.  Any term or provision of this  Agreement that is
invalid or unenforceable  in any situation in any jurisdiction  shall not affect
the validity or  enforceability  of the remaining terms and provisions hereof or
the validity or  enforceability  of the offending term or provision in any other
situation or in any other jurisdiction.

            (i)  Expenses.  Each of the parties will  bear  his or its own costs
and expenses  (including  legal fees and expenses)  incurred in connection  with
this Agreement and the transactions contemplated hereby.

            (j)  Construction.  The  parties  have  participated  jointly in the
negotiation  and  drafting  of this  Agreement.  In the  event an  ambiguity  or
question of intent or interpretation  arises,  this Agreement shall be construed
as if drafted jointly by the parties and no presumption or burden of proof shall
arise  favoring or  disfavoring  any party by virtue of the authorship of any of
the provisions of this Agreement.

            (k)  Specific  Performance.  Each of the  parties  acknowledges  and
agrees that the other party would be damaged irreparably in the event any of the
provisions of this Agreement are not performed in accordance with their specific
terms or otherwise are breached.  Accordingly,  each of the parties  agrees that
the other party shall be entitled to an  injunction  or  injunctions  to prevent
breaches of the  provisions of this Agreement and to enforce  specifically  this
Agreement and the terms and  provisions  hereof in any action  instituted in any
court of the United States or any state  thereof  having  jurisdiction  over the
parties  and the matter,  in  addition to any other  remedy to which they may be
entitled, at law or in equity.

            (l)  Individual  Capacity.  The parties hereto acknowledge and agree
that the  representations,  warranties  and agreements of Long contained in this
Agreement  are made by Long in his  individual  capacity  and not on  behalf  of
Allstar, and not in his capacity as an officer, director or employee of Allstar.

                                      *****





            IN WITNESS WHEREOF,  the undersigned have executed this Agreement as
of the date first above written.

                                    AMHERST COMPUTER PRODUCTS SOUTHWEST, LP

                                    By: /s/Gerald Birin

                                    Title: Chief Financial Officer



                                    /s/James H. Long

                                      James H. Long