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                                                                   EXHIBIT 10.63



May 28, 1998

Trevor Smith
ROSS Technology, Inc.
5316 Highway 290 West, Suite 500
Austin, Texas  78735

         Re:      Employee Retention and Severance Plan.

Dear Trevor:

As you know, ROSS recently announced that it is exploring various strategic
alternatives. We realize that the Company's current situation creates some
uncertainty, so we have developed an Employee Retention and Severance Plan to
provide you some security and incentive to continue your employment with the
Company, as well as with a potential successor to the Company or to the Viper
development design operations. You are a very valuable member of our team, and
we want you with us! The provisions of the Plan as they apply specifically to
you are summarized in this letter (which is the Individual Letter referred to in
the Plan). As with all compensation matters, your individual benefits under the
Plan are a private matter, and should not be discussed with other employees. Any
questions you may have should be discussed only with your immediate supervisor.

We have used some capitalized terms in this letter. Those terms have the
meanings set forth in the Plan. A copy of the Plan can be retrieved from the
Human Resources Department.

         1. Initial Retention Bonus.

         You will receive an initial Retention Bonus of $50,000. This payment is
         contingent upon your agreement (as evidenced by your signature below)
         to work at least until September 30, 1998 for the Company or any
         successor to the Company after a Change of Control (which includes,
         among other things, the sale of the Company as a whole or the sale of
         the Viper development design operations). You will receive this initial
         Retention Bonus within three days after you return a signed copy of
         this letter to me.




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         2. Additional Retention Bonus/Severance Payment In the Event of a
Change of Control.

                  (i) You will receive an additional combination Retention
         Bonus/Severance Payment of $200,000 with $75,000 payable on July 31,
         1998 and $125,000 payable on September 30, 1998 (which is in addition
         to any amounts that may be due to you under the Federal Worker
         Adjustment and Retraining Notification Act, if applicable) if there is
         a Change of Control of the Company and the following conditions are
         satisfied:

                           (a) you continue or accept, as applicable, employment
                  in Austin, Texas with the business that will continue the
                  operations of the Viper development design team (which may be
                  the Company or the successor to the Company or the design
                  team) at an aggregate base salary and target bonus no less
                  than your current aggregate base salary and target bonus with
                  the Company;

                           (b) you remain Continuously Employed by the Company
                  or that successor, as applicable, from now until September 30,
                  1998; and

                           (c) when your employment with the Company is
                  terminated, or on September 30, 1998, whichever is earlier,
                  you sign a release on a form provided by the Company,
                  releasing any claims you may have against the Company. A copy
                  of the form of release is included with this letter as Exhibit
                  A.

                  (i) The Company will waive some of the conditions set forth in
         the prior paragraph under certain circumstances. This will permit you
         to receive the Retention Bonus/Severance Payments set forth in the
         prior paragraph as long as you satisfy the remaining conditions.

                           (a) The Company will waive conditions (a) and (b) in
                  the prior paragraph if your employment is not continued (other
                  than for Just Cause) or you are not offered employment in
                  Austin, Texas by the business that will continue the
                  operations of the Viper Development team, or if the job which
                  continues or which you are offered has an aggregate base
                  salary and target bonus less than your current aggregate base
                  salary and target bonus with the Company.

                           (b) The Company will waive condition (b) in the prior
                  paragraph if, subsequent to a Change of Control, your
                  employment is terminated without Just Cause, if you quit for
                  Good Reason prior to September 30, 1998, or if you die or
                  become Disabled.




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                  (i) It is difficult to predict if or when a Change of Control
         will occur. Accordingly, if a Change of Control has not occurred by
         July 31, 1998 and/or September 30, 1998, you will receive the Retention
         Bonus/Severance Payments payable on those dates so long as (a) you are
         employed by the Company on the applicable date and (b) a Change of
         Control transaction is pending (i.e., an agreement has been signed
         which provides for a Change of Control transaction.) When your
         employment is subsequently terminated, or on September 30, 1998,
         whichever is earlier, you still must sign the release described above
         or you will have to refund these payments.

         1. Alternative Retention Bonus/Severance Payment In the Event a Change
of Control Does Not Occur.

         If a Change of Control of the Company does not occur or is not pending
         on July 31, 1998, and you are Continuously Employed with the Company
         through July 31, 1998, you will receive an alternative Retention
         Bonus/Severance Payment of $200,000 (which is in addition to any
         amounts that may be due to you under the Federal Worker Adjustment and
         Retraining Notification Act, if applicable) upon the termination of
         your employment without Just Cause or if you quit for Good Reason (even
         if this occurs prior to July 31, 1998). You will also need to sign the
         release mentioned above in order to receive these payments.

         Under these circumstances (and subject to executing the release), you
         will also be entitled to a continuation of your health benefits under
         the Company's medical and dental plans. Until July 31, 1999, the
         Company will pay for your health benefits coverage to the same extent
         as it has done up until now, and you will be required to make the same
         payments you have been making up until now. To be eligible for
         continued health benefits coverage, you may be required to make a COBRA
         election, even though the Company will be paying for all or part of
         your health benefits coverage as just described. Your health benefits
         coverage will cease, however, when you become covered under any group
         health plan maintained by another employer. If the Company is unable to
         provide you with continuing health coverage, the Company will pay you
         the cash value of such coverage through July 31, 1999. This amount will
         be determined by the Company.




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         2. Timing of Payments and Related Matters.

                  (i) Payments that are conditioned upon receipt in advance of a
         release will not be made until the later of the date that the release
         you sign becomes legally effective or the date specified in this letter
         for that payment (see paragraphs 2 and 3). If the Age Discrimination in
         Employment Act applies to you (that is, if you are at least forty years
         old), you will have twenty one days from the date you are presented
         with the release to decide whether to sign it and payment will occur
         eight days after you have executed the release and delivered it to the
         Company. If the ADEA does not apply to you, your release will be
         effective when you sign and deliver the release to the Company and
         payment will be made at that time.

                  (ii) We cannot predict when or if a Change of Control will
         occur, or whether other circumstances may arise that could permit or
         require a Retention Bonus/Severance Payment to be due you earlier than
         the specified dates set forth in this letter (for example, September
         30, 1998 under paragraph 2 and July 31, 1998 under paragraph 3). Thus,
         if the ADEA applies to you, we cannot tell you under all circumstances
         the date you will need to be presented a release to permit you to
         receive any required payments on a particular date. As an example,
         though, let's go through a few base cases:

                           (a) Let's assume a Change of Control has occurred,
                  you have continued your employment and we know you will be
                  entitled to receive a payment on September 30, 1998 under
                  paragraph 2, above. To get that payment, you need to execute a
                  release and have the release become effective. As described
                  above, if the ADEA applies to you, you will have twenty one
                  days to decide whether to sign the release and it will take
                  seven days to become effective. If you wanted to take the full
                  twenty one days to decide whether to sign the release and the
                  seven day delay on effectiveness was applicable, under those
                  circumstances, we would have to present you with the release
                  no later than September 2 so that a payment could be made on
                  September 30.

                           (b) Now let's assume everything is the same as in
                  clause (a), but we are unable to present you with the release
                  until September 30 (for example, because we don't know until
                  then that you will become entitled to the payment). Now, if
                  you sign the release on September 30 and the seven day delay
                  on effectiveness is not applicable to you, you can still get
                  your payment on September 30; if the seven day delay on
                  effectiveness applies, you would get your payment on October
                  8. If you wait to sign the release (remember, if the ADEA
                  applies to you, you have twenty one days to decide whether to
                  sign it), add one additional day until payment can be made for
                  each day you wait until you sign.


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                           (c) Finally, let's assume there has been no Change of
                  Control, you have continued your employment and we know you
                  will be entitled to receive a payment on July 31, 1998 under
                  paragraph 3, above. Everything about the analysis is the same
                  as in clause (a) and (b), except change the dates and use July
                  31, 1998 as the base for the calculations.

                  (i) None of the payments under this letter will be reduced by
         any payments you may otherwise receive pursuant to other employment.
         Severance Payments will supersede any other severance payments you may
         otherwise be entitled to receive from the Company under any other
         severance plan or policy.

         1. Honoring This Letter.

         If there is a Change of Control and you are offered employment in
         Austin, Texas by the business that will continue the operations of the
         Viper development design team (which may be the Company or the
         successor to the Company or the design team) at an aggregate base
         salary and target bonus no less than your current aggregate base salary
         and target bonus with the Company, and you do not accept that position
         or you fail to remain Continuously Employed by the Company or such
         successor, as applicable, until September 30, 1998 (other than because
         you are terminated without Just Cause or quit for Good Reason), you
         must refund any Retention Bonuses or Severance Payments you received
         under any paragraph of this letter. You must also refund any Retention
         Bonuses/Severance Payments you receive pursuant to paragraph 2(iii) if
         you do not subsequently execute the required release.

         2. Confidential Material.

         Your receipt of Retention Bonuses or a Severance Payment is conditioned
         on your refraining from disclosing any confidential material or
         information of the Company. The Company may sue you because you
         disclose, or to prevent your disclosure of, confidential material or
         information.




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         3. Summary Plan Description; ERISA Rights; Miscellaneous Provisions.

         The Plan is a welfare benefit plan within the meaning of the Federal
         Employee Retirement Income Security Act of 1974 ("ERISA"). This letter
         constitutes the Summary Plan Description required under ERISA. This
         letter merely summarizes the detailed and technical provisions of the
         Plan. In the event of a conflict between this letter and the Plan, the
         terms and provisions of the Plan will control. You may obtain a copy of
         the Plan from the Human Resources Department. Attached to this letter
         is an Exhibit B describing your rights under ERISA. The Plan contains a
         claims procedure and an arbitration provision.


                                                    Very truly yours,


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                                                    Jack W. Simpson, Sr.
                                                    President and CEO
AGREED TO AND ACCEPTED:

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Name
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Date




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