Document:

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                                                                 Exhibit 10.77

[LETTERHEAD OF INFORMIX]

July 31, 2000

Mr. Peter Gyenes
40 Heath Hill
Brookline, MA 02146

Dear Peter:

This letter confirms the recent actions of the Compensation Committee of the
Board of Directors. Effective July 14, 2000, your annual base compensation is
$600,000, payable in equal, semi-monthly installments. You will also
participate in the Executive Incentive Compensation Plan, effective July 1,
2000, at a target incentive of 100% of this annual base. For fiscal 2000, 25%
of this annual target incentive shall be guaranteed.

The Board of Directors has approved a non-qualified stock option under the
Corporation's 1994 Stock Option and Award Plan of 1,500,000 shares, priced on
July 13, 2000 at $4.9375. Twenty-five percent (25%) of these options shall be
exercisable on or after the first anniversary of the effective date, and an
additional 2.08% shall be exercisable on or after each one-month anniversary
thereafter.

You will also receive a retention bonus of $875,000, payable immediately,
with an equal retention bonus payment of $875,000 to be paid on April 15,
2001, pending your active continuance in your executive management position
at that time. Your involuntary termination or a Change of Control prior to
April 15, 2001 will accelerate the second payment to the date of your actual
termination.

For the Compensation Committee

/s/ Wayne E. Page

Wayne E. Page
Vice President-Human Resources<PAGE>

                                                                   EXHIBIT 10.78

                              INFORMIX CORPORATION

                    CHANGE OF CONTROL AND SEVERANCE AGREEMENT

          This Change of Control and Severance Agreement (the "Agreement") is
made and entered into by and between Peter Gyenes (the "Executive") and Informix
Corporation (the "Company"), effective as of the last date set forth by the
signatures of the parties below (the "Effective Date").

                                    RECITALS

          A.        It is expected that the Company from time to time will
consider the possibility of an acquisition by another company or other Change of
Control (as defined below). The Board of Directors of the Company (the "Board")
recognizes that such consideration, and the possibility that the Executive's
employment could be terminated by the Company for a reason other than for cause,
can be distractions to the Executive and can cause the Executive to consider
alternative employment opportunities. The Board has determined that it is in the
best interests of the Company and its stockholders to assure that the Company
will have the continued dedication and objectivity of the Executive,
notwithstanding the possibility, threat or occurrence of a Change of Control of
the Company or the termination by the Company of the Executive's employment for
a reason other than for cause.

          B.        The Board believes that it is in the best interests of the
Company and its stockholders to provide the Executive with an incentive to
continue his or her employment with the Company, or a wholly-owned subsidiary of
the Company, as the case may be, and to motivate the Executive to maximize the
value of the Company upon a Change of Control for the benefit of its
stockholders.

          C.        The Board believes that it is imperative to provide the
Executive with certain benefits upon a Change of Control or upon the termination
by the Company of the Executive's employment for a reason other than cause,
thereby encouraging the Executive to remain with the Company notwithstanding the
possibility of a Change of Control or termination of employment for a reason
other than for cause.

          The Company and the Executive hereby agree as follows:

          1.        TERM OF AGREEMENT. This Agreement shall terminate upon the
date that all obligations of the Company and the Executive with respect to this
Agreement have been satisfied.

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          2.        AT-WILL EMPLOYMENT. The Company and the Executive
acknowledge that the Executive's employment is and shall continue to be at-will,
as defined under applicable law, and may be terminated at any time by either
party, with or without cause.

          3.        CHANGE OF CONTROL. In the event a Change of Control occurs
within six months following the effective date of options granted to the
Executive to purchase the Company's common stock, and if the Executive is
employed by the Company as of the date of the Change of Control, the Executive's
stock options shall have their vesting accelerated as to two years' additional
vesting. In the event that stock option vesting is accelerated pursuant to the
preceding sentence, the remaining stock options, if any, shall continue to vest
at a monthly rate equal to the total number of shares originally subject to the
option divided by the number of months in the original vesting schedule. In the
event a Change of Control occurs on or after six months following the effective
date of options granted to the Executive to purchase the Company's common stock,
and if the Executive is employed by the Company as of the date of the Change of
Control, the Executive's Stock Options shall have their vesting accelerated in
full so as to become 100% vested.

          For the purposes of this Agreement, "Change of Control" shall mean:

                    (a)       the approval by the stockholders of the Company of
a merger or consolidation of the Company with any other corporation, other than
a merger or consolidation which would result in the voting securities of the
Company outstanding immediately prior thereto continuing to represent (either by
remaining outstanding or by being converted into voting securities of the
surviving entity) fifty percent (50%) or more of the total voting power
represented by the voting securities of the Company or such surviving entity
outstanding immediately after such merger or consolidation; or

                    (b)       any approval by the stockholders of the Company of
a plan of complete liquidation of the Company or an agreement for the sale or
disposition by the Company of all or substantially all of the Company's assets;
or

                    (c)       any "person" (as that term is used in Sections
13(d) and 14(d) of the Securities Exchange Act of 1934, as amended) becoming the
"beneficial owner" (as defined in Rule 13d-3 under the Securities Exchange Act
of 1934, as amended), directly or indirectly, of securities of the Company
representing 50% or more of the total voting power represented by the Company's
then outstanding voting securities; or

                    (d)       a change in the composition of the Board, as a
result of which fewer than a majority of the directors are Incumbent Directors.
"Incumbent Directors" shall mean directors who either: (a) are directors of the
Company as of the Effective Date; or (b) are elected, or nominated for election,
to the Board with the affirmative votes of at least a majority of those
directors whose election or nomination was not in connection with any
transaction described in subsections (a), (b), or (c) above, or in connection
with an actual or threatened proxy contest relating to the election of directors
of the Company.

                                       -2-
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          4.        GOLDEN PARACHUTE EXCISE TAXES. Anything in this Agreement to
the contrary notwithstanding, in the event it shall be determined that any
payment or distribution, or any acceleration of vesting of any benefit or award,
by the Company or its affiliated companies to or for the benefit of the
Executive, payable within the meaning of Section 280G of the Internal Revenue
Code (the "Code") (whether paid or payable, distributed or distributable or
accelerated or subject to acceleration pursuant to the terms of this Agreement
or otherwise, but determined without regard to any additional payments required
under this Section 4) (a "Payment") would be subject to the excise tax imposed
by Section 4999 of the Code, or any interest or penalties are incurred by the
Executive with respect to such excise tax (such excise tax, together with any
such interest and penalties, are hereinafter collectively referred to as the
"Excise Tax"), then the Executive shall be entitled to receive an additional
payment (a "Gross-Up Payment") on an amount such that after payment by the
Executive of all taxes imposed upon the Gross-Up Payment and any interest or
penalties imposed with respect to such taxes, the Executive retains an amount of
the Gross-Up Payment equal to the sum of: (a) the Excise Tax imposed upon the
Payments; and (b) the product of any deductions disallowed because of the
inclusion of the Gross-Up Payment in the Executive's adjusted gross income and
the highest applicable marginal rate of federal income taxation for the calendar
year in which the Gross-Up Payment is to be made. For purposes of determining
the amount of the Gross-Up Payment, the Executive shall be deemed to have: (a)
paid federal income taxes at the highest marginal rates of federal income
taxation for the calendar year in which the Gross-Up Payment is to be made; (b)
paid applicable state and local income taxes at the highest rate of taxation for
the calendar year in which the Gross-Up Payment is to be made, net of the
maximum reduction in federal income taxes which could be obtained from deduction
of such state and local taxes; and (c) otherwise allowable deductions for
federal income tax purposes at least equal to those which would be disallowed
because of the inclusion of the Gross-Up Payment in the Executive's adjusted
gross income. The payment of a Gross-Up Payment under this Section 4 shall in no
event be conditioned upon the Executive's termination of employment or the
receipt of severance benefits under this Agreement.

          5.        SEVERANCE.

                    (a)       If, within one year of a Change of Control, the
Executive's employment is terminated either by the Executive for any reason or
by the surviving entity for any reason other than for Cause (as defined below),
the Executive shall receive severance in the amount of two years' base salary
plus two years' on target earnings.

                    (b)       If the Executive's employment is terminated by the
Company for any reason other than for Cause, the Executive shall receive
severance in the amount of two years' base salary.

                                       -3-
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                    (c)       If the Executive's employment is terminated by the
Company for Cause, or the Executive voluntarily resigns, the Executive shall not
receive severance.

                    (d)       For purposes of this Agreement, "Cause" shall mean
the occurrence of one or more of the following: (i) Executive's conviction by,
or entry of a plea of guilty or NOLO CONTENDERE in, a court of competent
jurisdiction for any crime which constitutes a felony in the jurisdiction in
which the conduct alleged to constitute the felony occurred; (ii) Executive's
misappropriation of funds or property or commission of an act of fraud, whether
prior or subsequent to the Effective Date; (iii) gross negligence or
recklessness by the Executive in the scope of the Executive's services to the
Company; (iv) a breach by the Executive of a material provision of this
Agreement which is not cured within 30 days of notice; (v) a willful failure by
the Executive substantially to perform his or her duties and responsibilities as
an employee after notice of such failure; or (vi) a material breach by the
Executive of the Company's policies or procedures.

          6.        ATTORNEY FEES, COSTS AND EXPENSES. The Company promptly
shall reimburse the Executive, on a monthly basis, for the reasonable attorney
fees, costs and expenses incurred by the Executive in connection with any action
brought by Executive to enforce his or her rights under this Agreement,
regardless of the outcome of the action.

          7.        SUCCESSORS.

                    (a)       COMPANY'S SUCCESSORS. Any successor to the Company
(whether direct or indirect and whether by purchase, merger, consolidation,
liquidation or otherwise) to all or substantially all of the Company's business
and/or assets shall assume the obligations under this Agreement and agree
expressly to perform the obligations under this Agreement in the same manner and
to the same extent as the Company would be required to perform such obligations
in the absence of a succession. For all purposes under this Agreement, the term
"Company" shall include any successor to the Company's business and/or assets
which executes and delivers the assumption agreement described in this Section
5(a), or which becomes bound by the terms of this Agreement by operation of law.

                    (b)       EXECUTIVE'S SUCCESSORS. The terms of this
Agreement and all rights of the Executive hereunder shall inure to the benefit
of, and be enforceable by, the Executive's personal or legal representatives,
executors, administrators, heirs, distributees, devisees and legatees.

          8.        MISCELLANEOUS PROVISIONS.

                    (a)       WAIVER. No provision of this Agreement shall be
modified, waived or discharged unless the modification, waiver or discharge is
agreed to in writing and signed by the Executive and by an authorized officer of
the Company (other than the Executive). No waiver by either party of any breach
of, or of compliance with, any

                                       -4-
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condition or provision of this Agreement by the other party shall be considered
a waiver of any other condition or provision or of the same condition or
provision at another time.

                    (b)       WHOLE AGREEMENT. No agreements, representations or
understandings (whether oral or written and whether express or implied) which
are not expressly set forth in this Agreement have been made or entered into by
either party with respect to the subject matter hereof. This Agreement
represents the entire understanding of the Company and the Executive with
respect to the subject matter of this Agreement and this Agreement supersedes
all prior agreements, arrangements and understandings regarding the subject
matter of this Agreement. If stock option vesting acceleration is triggered
pursuant to this Agreement, the Executive agrees that he or she shall not be
entitled to any additional stock option vesting pursuant to a prior agreement,
arrangement or understanding.

                    (c)       CHOICE OF LAW. The validity, interpretation,
construction and performance of this Agreement shall be governed by the laws of
the State of California.

                    (d)       SEVERABILITY. The invalidity or unenforceability
of any provision or provisions of this Agreement shall not affect the validity
or enforceablity of any other provision hereof, which shall remain in full force
and effect.

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

          IN WITNESS WHEREOF, each of the parties has executed this Agreement,
in the case of the Company by its duly authorized officer, as of the day and
year set forth below.

COMPANY                                     INFORMIX CORPORATION

                                            /s/ Gary Lloyd
                                            ------------------------------

                                            Dated:  Effective August 28, 2000

EXECUTIVE                                   /s/ Peter Gyenes
                                            ------------------------------

                                            Dated:  Effective August 28, 2000

                                       -5-

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