Exhibit 4.28
                           SECURED PROMISSORY NOTE

 $360,000.00                                         Phoenix, Arizona
                                                     March 25, 1999

           FOR  VALUE  RECEIVED,   PC  DYNAMICS  OF   TEXAS,  INC.  a   Texas
 corporation ("Borrower"), promises  to pay to  the order  of FINOVA  CAPITAL
 CORPORATION, a Delaware corporation ("FINOVA"). at its offices at  355 South
 Grand Avenue, Suite 2400,  Los Angeles, California 90071,  or at  such other
 place or places as FINOVA  may from time to  time designate in writing,  the
 principal sum of  Three Hundred Sixty  Thousand Dollars  ($360,000.00), plus
 interest in the manner  and upon the terms  and conditions set forth  below.
 This Secured Promissory Note ("Note") is made pursuant to that certain  Loan
 and Security Agreement  of even date  between the FINOVA  and  Borrower (the
 "Loan Agreement"), the provision  of which are  incorporated herein  by this
 reference.  Capitalized terms herein, unless otherwise noted, shall have the
 meaning set forth in the Loan Agreement.

 1.0  Schedule of Payments: Rate and Payment of Interest: Prepayment.

      1.1  This Note shall be payable as follows:

            a.   Twenty-three (23) equal  successive monthly installments  of
 principal of Six Thousand Dollars ($6000.00)  each on the first day of  each
 month, beginning May 1,1999, and continuing through and including April  30,
 2001; and

            b.   A final  installment  of  Two  Hundred  Twenty-Two  Thousand
 Dollars ($222,000.00) on the May 1, 2001, together with accrued interest  on
 the principal balance from time to time remaining unpaid, payable monthly on
 the first day of each and every month, beginning March 25, 1999.

      1.2   Prepayment may be made under this Note in whole but not in  part,
 subject to the Termination  set forth in the  Loan Agreement, provided  that
 such prepayment is preceded  by not less than  five (5) business days  prior
 written notice to FINOVA and accompanied  by all accrued by unpaid  interest
 and the  full  amount of  the  applicable Termination  Fee.  Notwithstanding
 anything herein  to  the  contrary,  in the  event  the  Loan  Agreement  is
 terminated by Borrower, by  FINOVA or by any  other person at anytime,  then
 the entire unpaid principal balance of this Note, together with all  accrued
 and unpaid interest hereon and the full amount of the applicable Termination
 Fee, shall become immediately due and payable in full on the effective  date
 of such termination, without presentment, notice or demand of any kind.

      1.3   Interest shall be  computed on the  basis of a  360-day year  for
 the actual number of  days elapsed, and shall  be at the  rate of three  (3)
 percentage points above the Prime Rate (as hereinafter defined), computed on
 the basis of  a 360-day  year; provided,  however, upon  the occurrence  and
 during the  continuance of  an event  of default  (as hereinafter  defined),
 interest shall accrue on the outstanding principal balance of this Note at a
 default rate (the "Default  Rate") of four (4)  percentage points above  the
 Prime Rate, and shall be payable on demand. "Prime Rate" means, for any day,
 the rate  of interest  per annum  (over a  year  of 360 days)  announced  by
 Citibank, NA. (the "Bank"), from  time to time, as  its "base rate" (or  any
 successor thereto) in effect on such day.  The Prime Rate is not necessarily
 the lowest  rate  charged by  the  Bank.  The applicable  rate  of  interest
 assessed hereunder  will  be  increased  or  decreased  from  time  to  time
 hereafter in an amount equal to  any increase or decrease hereafter made  by
 the Bank in the Prime Rate. A change in the Prime Rate shall be effective on
 the first day following such change.
<PAGE>

      2.1  The  occurrence  of  any   one  of  the  following  events   shall
 constitute a default by Borrower under  this Note (hereinafter an "Event  of
 Default"): (a)  if  Borrower  fails  to pay  to  FINOVA  an  installment  of
 principal or interest hereunder when due;  (b) if Borrower fails to pay  any
 of its Obligations (as defined in the Loan Agreement) to FINOVA when due and
 payable or declared due  and payable; (c) if  Borrower fails or  neglects to
 perform,  keep  or  observe  any  term,  provision,  covenant,  warranty  or
 representation contained in this Note or  the Loan Agreement (other  than as
 referred to  in (a)  or (b)  of this  paragraph), which  is required  to  be
 performed, kept or  observed by Borrower  or if a  default occurs under  the
 Loan Agreement; or (d) the  occurrence of a default  or an event of  default
 under any agreement, instrument or document  heretofore, now or at any  time
 or times hereafter delivered  to FINOVA by Borrower  or by any guarantor  of
 part or all of Borrowers Obligations to FINOVA.

      2.2   Upon  the occurrence  of  any  Event  of  Default  hereunder,  in
 addition to FINOVA's  right to  charge interest  on the  Obligations at  the
 Default Rate: (a) at the option of  FINOVA, the entire unpaid amount of  all
 of the Obligations, including without limitation the Termination Fee,  shall
 become immediately due and payable without  demand, notice or legal  process
 of any kind; (b) FINOVA may, at its option, without demand, notice or  legal
 process of any  kind, exercise any and all rights and remedies granted to it
 by the Loan Agreement  or by any other  agreement now or hereafter  existing
 between FINOVA and Borrower or between  FINOVA and any guarantor of part  or
 all of Borrowers  liabilities to FINOVA;  and (c) FINOVA  may at its  option
 exercise from time  to time any  other rights and  remedies available to  it
 under the Uniform Commercial Code or other law of the State of Arizona.

      2.3   The remedies  of  FINOVA  as provided  herein  and  in  the  Loan
 Agreement shall be cumulative and concurrent, and may be pursued singularly,
 successively, or  together, at  the sole  discretion of  FINOVA. No  act  of
 omission or  commission of  FINOVA, including  specifically any  failure  to
 exercise any right, remedy or  recourse, shall be deemed  to be a waiver  or
 release of the same, such  waiver or release to  be effected only through  a
 written document executed by FINOVA and then only to the extent specifically
 recited therein. A waiver or release  with reference to any one event  shall
 not be construed as continuing, as a bar to,  or as a waiver or release  of;
 any subsequent right, remedy or recourse as to a subsequent event.

 3.0  General Provisions.

      3.1   Borrower warrants  and represents  to  FINOVA that  Borrower  has
 used and will  continue to use  the loans and  advances represented by  this
 Note solely for proper business purposes, and consistent with all applicable
 laws and statutes.

      3.2   This Note  is secured  by the  Collateral described  in the  Loan
 Agreement.

      3.3   Borrower  waives  presentment,  demand  and  protest,  notice  of
 protest, notice  of  presentment  and  all  other  notices  and  demands  in
 connection with  the enforcement  of FINOVA's  rights hereunder,  except  as
 specifically provided and called for by  this Note, and hereby consents  to,
 and waives  notice  of, the  release,  addition, or  substitution,  with  or
 without consideration, of any collateral or of any person liable for payment
 of this  Note.  Any  failure  of FINOVA  to  exercise  any  right  available
 hereunder or otherwise shall not  be construed as a  waiver of the right  to
 exercise the same or as a waiver of any other right at any other time,
<PAGE>
      3.4   If this  Note is not paid when due  or upon the occurrence of  an
 Event of Default, Borrower further promises to pay all costs of  collection,
 foreclosure fees, attorneys fees and expert witness fees incurred by FINOVA,
 whether or not suit  is filed hereon,  and the fees,  costs and expenses  as
 provided in the Loan Agreement.

      3.5   The  contracted for  rate of  interest of  the loan  contemplated
 hereby, without limitation, shall consist of the following: (i) the interest
 rate set forth  on the  Schedule, calculated  and applied  to the  principal
 balance of this Note  in accordance with the  provisions of this Note:  (ii)
 interest after an Event  of Default, calculated and  applied to the  amounts
 due under this Note in accordance with the provisions hereof; and (iii)  all
 Additional Sums (as  herein defined),  if any.   Borrower agrees  to pay  an
 effective contracted for  rate of interest  which is the  sum of the  above-
 referenced elements. All  examination fees, attorneys  fees, expert  witness
 fees, letter  of  credit fees,  collateral  monitoring fees,  closing  fees,
 facility fees, Termination  Fees, Minimum Interest  Charges, other  charges,
 goods, things in action or any other sums or things of value paid or payable
 by Borrower (collectively, the "Additional Sums"), whether pursuant to  this
 Note, the Loan Agreement  or any other documents  or instruments in any  way
 pertaining to this lending  transaction, or otherwise  with respect to  this
 lending transaction,  that under  any applicable  law may  be deemed  to  be
 interest with respect to  this lending transaction, for  the purpose of  any
 applicable law that may limit the  maximum amount of interest to be  charged
 with respect to this lending transaction,  shall be payable by Borrower  as,
 and shall be deemed to be,  additional interest and for such purposes  only,
 the agreed  upon and  "contracted  for rate  of  interest" of  this  lending
 transaction shall  be  deemed  to  be increased  by  the  rate  of  interest
 resulting from the inclusion of the Additional Sums.

      3.6   It is the intent  of the parties to comply with the usury law  of
 the State of Arizona (the "Applicable Usury Law"). Accordingly, it is agreed
 that notwithstanding any provisions to the contrary in this Note, or in  any
 of the documents securing payment Hereof or otherwise relating hereto, in no
 event shall this Note  or such documents require  the payment or permit  the
 collection of interest in excess of  the maximum Interest Rate, then in  any
 such event (1) the provisions of the paragraph shall govern and control, (2)
 neither Borrower nor any other person or entity now or hereafter liable  for
 the payment hereof shall be obligated tp pay the amount of such interest  to
 the extent that it is in excess of  the Maximum Interest Rate, (3) any  such
 excess which may  have been collected  shall be either  applied as a  credit
 against the then unpaid principal amount hereof or refunded to Borrower,  at
 FINOVA's  option,  and  (4)  the  effective   rate  of  interest  shall   be
 automatically reduced to the  Maximum Interest Rate.  It is further  agreed,
 without limiting  the  generality  of the  foregoing,  that  to  the  extent
 permitted by  the Applicable  Usury Law;  (x) all  calculations of  interest
 which are made for the purpose of determining whether such rate would exceed
 the Maximum Interest Rate shall be made by amortizing, prorating, allocating
 and spreading  during  the  period of  the  full  stated term  of  the  loan
 evidenced hereby,  all  interest at  any  time contracted  for,  charged  or
 received from Borrower or otherwise in connection with such loan; and (y) in
 the event that the effective rate of interest on the loan should at any time
 exceed the Maximum Interest Rate, such excess interest that would  otherwise
 have been collected  had there  been no  ceiling imposed  by the  Applicable
 Usury Law  shall be  paid to  FINOVA from  time  to time,  if and  when  the
 effective interest  rate  on  the loan  otherwise  fall  below  the  Maximum
 Interest Rate, until  the entire amount  of interest  which would  otherwise
 have been collected  had there  been no  ceiling imposed  by the  Applicable
 Usury Law has been paid in  full.  Borrower further  agrees that should  the
 Maximum Interest Rate be increased at any time hereafter because of a change
 in the  Applicable Usury  Law, then  to  the extent  not prohibited  by  the
 Applicable Usury  Law,  such  increases  shall  apply  to  all  indebtedness
 evidenced hereby regardless of when incurred;  but, again to the extent  not
 prohibited by the Applicable Usury Law, should the maximum Interest Rate  be
 decreased because of a  change in the Applicable  Usury Law, such  decreases
 shall not  apply to  the indebtedness  evidenced hereby  regardless of  when
 incurred.
<PAGE>
      3.7   FINOVA may at any time transfer this Note and FINOVA's rights  in
 any or all  collateral securing this  Note, and FINOVA  thereafter shall  be
 relieved from all liability  with respect to  such collateral arising  after
 the date of such transfer.

      3.8   This  Note  shall   be  binding  upon  Borrower  and  its   legal
 representatives, successors and assigns Wherever possible, each provision of
 this Note shall be interpreted in such manner  as to  be effective and valid
 under  applicable law, but if  any provision of the Note shall be prohibited
 by  or  invalid  under such  law,  such  provision  shall  be severable, and
 be ineffective  to  the  extent  of such prohibition  or invalidity, without
 invalidating the remaining provision of this Note.

      THIS  NOTE HAS  BEEN DELIVERED  FOR ACCEPTANCE  BY  FINOVA IN  PHOENIX,
 ARIZONA AND  SHALL BE  GOVERNED  BY AND  CONSTRUED  IN ACCORDANCE  WITH  THE
 INTERNAL LAWS (AS OPPOSED TO THE  CONFLICTS OF LAW PROVISIONS) OF  THE STATE
 OF ARIZONA, AS  THE SAME  MAY FROM  TIME TO  TIME BE  IN EFFECT,  INCLUDING,
 WITHOUT LIMITATION,  THE  UNIF6RM COMMEBOIAL  CODE  AS ADOPTED  IN  ARIZONA.
 BORROWER HEREBY (I) IRREVOCABLY SUBMITS TO THE JURISDICTION OF ANY  STATE OR
 FEDERAL COURT  LOCATED  IN  MARICOPA  COUNTY, ARIZONA  OVER  ANY  ACTION  OR
 PROCEEDING TO ENFORCE OR DEFEND ANY  MATTER ARISING FROM OR RELATED  TO THIS
 NOTE; (ii) WAIVES PERSONAL SERVICE OF ANY AND ALL PROCESS UPON BORROWER, AND
 CONSENTS THAT ALL SUCH  SERVICE OF PROCESS BE  MADE BY MESSENGER,  CERTIFIED
 MAIL OR REGISTERED MAIL DIRECTED TO BORROWER AT THE ADDRESS SET  FORTH BELOW
 AND SERVICE SO  MADE SHALL BE  DEEMED TO  BE COMPLETED  UPON THE EARLIER  OF
 ACTUAL RECEIPT OR THREE  (3) DAYS AFTER THE  SAME SHALL HAVE BEEN  POSTED TO
 BORROWER'S ADDRESS; (iii) IRREVOCABLY WAIVES, TO THE FULLEST EXTENT BORROWER
 MAYEFFECTIVELY  DO  SO,  THE  DEFENSE  OF  AN  INCONVENIENT  FORUM   TO  THE
 MAINTENANCE OF  ANY SUCH  ACTION OR  PROCEEDING; (iv)  AGREES  THAT A  FINAL
 JUDGMENT IN ANY  SUCH ACTION OR  PROCEEDING SHALL BE  CONCLUSIVE AND MAY  BE
 ENFORCED IN ANY OTHER JURISDICTION BY  SUIT ON THE JUDGMENT OR IN  ANY OTHER
 MANNER PROVIDED BY  LAW; (v)  AGREES NOT TO  INSTITUTE ANY  LEGAL ACTION  OR
 PROCEEDING AGAINST FINOVA OR ANY OF FINOVA'S DIRECTORS, OFFICERS, EMPLOYEES,
 AGENTS OR PROPERTY, CONCERNING ANY MATTER ARISING OUT OF OR RELATING TO THIS
 NOTE IN ANY COURT  OTHER THAN ONE LOCATED  IN MARICOPA COUNTY, ARIZONA;  AND
 (vi) IRREVOCABLY WAIVES ANY  RIGHTTO A TRIAL BY  JURY IN ANY ACTION  ARISING
 UNDER OR  IN CONNECTION  WITH THIS  NOTE. NOTHING  IN  THIS PARAGRAPH  SHALL
 AFFECT OR IMPAIR FINOVAS RIGHTTO SERVE LEGAL PROCESS IN ANY MANNER PERMITTED
 BY LAW  OR  FINOVA'S  RIGHT TO  BRING  ANY  ACTION OR  AGAINST  BORROWER  OR
 BORROWERS PROPERTY IN THE COURTS OF ANTOTHER JURISDICTION.

                                 PC DYNAMICS OF TEXAS, INC.,
                                 a Texas corporation

                                 By: /s/
                                     --------------------------
                                     D. Ronald Allen, President
                                     FEIN: 75-2808489
                                     10501 FM 720 East
                                     Frisco, Texas 75034