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                                                                    EXHIBIT 10.5


                 2000 NON-EMPLOYEE DIRECTORS' STOCK OPTION PLAN
                                       OF
                                     CEPHEID


      1.    PURPOSES OF THE PLAN

            The purposes of the 2000 Non-Employee Directors' Stock Option Plan
of Cepheid, a California corporation, are: (a) to encourage Nonemployee
Directors to accept or continue their association with the Company; and (b) to
increase the interest of Nonemployee Directors in the Company's operations and
increased profits through participation in the growth in value of the Common
Stock of the Company.

      2.    DEFINITIONS

            As used herein, the following definitions shall apply:

            (a)   "Administrator" shall mean the entity, either the Board or a
committee appointed by the Board, responsible for administering this Plan, as
provided in Section 5.

            (b)   "Affiliate" shall mean a parent or subsidiary corporation as
defined in the applicable provisions of the Code.

            (c)   "Annual Option" shall have the meaning set forth in Section
6(b).

            (d)   "Board" shall mean the Board of Directors of the Company, as
constituted from time to time.

            (e)   "Code" shall mean the Internal Revenue Code of 1986, as
amended.

            (f)   "Common Stock" shall mean the Common Stock of the Company.

            (g)   "Company" shall mean Cepheid, a California corporation.

            (h)   "Director Fee" shall mean the cash amount, if any, a
Nonemployee Director shall be entitled to receive for serving as a director of
the Company in any fiscal year.


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            (i)   "Fair Market Value" shall mean, as of the date in question,
the last transaction price quoted by the NASDAQ National Market System on the
date of grant; provided, however, that if the Common Stock is not traded on such
market system or the foregoing shall otherwise be inappropriate, then the Fair
Market Value shall be determined by the Administrator in good faith at its sole
discretion and on such basis as it shall deem appropriate. Such determination
shall be conclusive and binding on all persons.

            (j)   "Initial Option" shall have the meaning set forth in Section
6(a).

            (k)   "Nonemployee Director" shall mean any person who is a member
of the Board but is not an employee of the Company or any Parent or Subsidiary
of the Company and has not been an employee of the Company or any Parent or
Subsidiary of the Company at any time during the preceding 12 months.

            (l)   "Option" shall mean a stock option granted pursuant to this
Plan.

            (m)   "Option Agreement" shall mean the written agreement described
in Section 6(c) evidencing the grant of an Option to a Nonemployee Director and
containing the terms, conditions and restrictions pertaining to such Option.

            (n)   "Option Shares" shall mean the Shares subject to an Option
granted under this Plan.

            (o)   "Optionee" shall mean a Nonemployee Director who holds an
Option.

            (p)   "Parent" shall mean a "parent corporation," whether now or
hereafter existing, as defined in Section 424(e) of the Code.

            (q)   "Plan" shall mean this 1999 Nonemployee Directors Stock Option
Plan of Cepheid, as it may be amended from time to time.

            (r)   "Rule 16b-3" shall mean Rule 16b-3 promulgated by the
Securities and Exchange Commission, or any successor rule thereto.

            (s)   "Section" unless the context clearly indicates otherwise,
shall refer to a Section of this Plan.

            (t)   "Share" shall mean a share of Common Stock, as adjusted in
accordance with Section 7(a).




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            (u)   "Subsidiary" shall mean a "subsidiary corporation" of the
Company, whether now or hereafter existing, within the meaning of Section 424(f)
of the Code, but only for so long as it is a "subsidiary corporation".

      3.    ELIGIBLE PERSONS

            Every person who at the date of grant of an Option is a Nonemployee
Director is eligible to receive Options under this Plan.

      4.    STOCK SUBJECT TO THIS PLAN

            Subject to Section 7(a) of this Plan, the maximum aggregate number
of Shares which may be issued on exercise of Options granted pursuant to this
Plan is 200,000 Shares. The Shares covered by the portion of any grant under the
Plan which expires unexercised shall become available again for grants under the
Plan.

      5.    ADMINISTRATION

            (a)   This Plan shall be administered by the Board, or by a
committee (the "Committee") of at least two Board members to which
administration of the Plan is delegated (in either case, the "Administrator"),
in accordance with the requirements of Rule 16b-3.

            (b)   Subject to the other provisions of this Plan, the
Administrator shall have the authority, in its sole discretion: (i) to determine
the Fair Market Value of the Shares subject to Option; (ii) to interpret this
Plan; (iii) to prescribe, amend and rescind rules and regulations relating to
this Plan; (iv) to defer (with the consent of the Optionee) or accelerate the
exercise date of any Option; (v) to authorize any person to execute on behalf of
the Company any instrument evidencing the grant of an Option; and (vi) to make
all other determinations deemed necessary or advisable for the administration of
this Plan. The Administrator may delegate nondiscretionary administrative duties
to such employees of the Company as it deems proper.

            (c)   All questions of interpretation, implementation and
application of this Plan shall be determined by the Administrator. Such
determination shall be final and binding on all persons.

      6.    GRANT OF OPTIONS

            (a)   Grant for Initial Election or Appointment to Board. Subject to
the terms and conditions of this Plan, if any person who is not an officer or
employee of the Company is first elected or appointed as a member of the Board
and is otherwise



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considered a "Nonemployee Director" as defined herein, then the Company shall
grant to such Nonemployee Director on such day an Option to purchase 15,000
Shares ("Initial Option") at an exercise price equal to the Fair Market Value of
such Shares on the date of such Initial Option grant, subject to the limitation
of Section 7(i).

            (b)   Grant for Re-election to Board. Subject to the terms and
conditions of this Plan, on the date of the first meeting of the Board
immediately following each annual meeting of stockholders of the Company (even
if held on the same day as the meeting of stockholders) the Company shall grant
to each Nonemployee Director then in office for longer than six months, an
Option to purchase 5,000 shares (the "Annual Option") at an exercise price equal
to the Fair Market Value of such Shares.

            (c)   No Option shall be granted under this Plan after ten years
from the date of adoption of this Plan by the Board. Each Option shall be
evidenced by a written Option Agreement, in form and substance satisfactory to
the Company, executed by the Company and the Optionee. Failure by the Company,
the Nonemployee Director, or both to execute an Option Agreement shall not
invalidate the granting of an Option; however, the Option may not be exercised
until the Option Agreement has been executed by both parties.

      7.    TERMS AND CONDITIONS OF OPTIONS

            Each Option granted under this Plan shall be subject to the terms
and conditions set forth in this Section 7.

            (a)   Changes in Capital Structure. Subject to subsection 7(b), if
the Common Stock is changed by reason of a stock split, reverse stock split,
stock dividend, or recapitalization, or converted into or exchanged for other
securities as a result of a merger, consolidation, or reorganization,
appropriate adjustments shall be made in: (i) the number and class of shares of
Common Stock subject to this Plan and each Option outstanding under this Plan;
and (ii) the exercise price of each outstanding Option; provided, however, that
the Company shall not be required to issue fractional shares as a result of any
such adjustment. Each such adjustment shall be subject to approval by the
Administrator in its sole discretion.

            (b)   Time of Option Exercise. Subject to the other provisions of
this Plan, each Option shall be for a term of ten years. Each Option shall be
exercisable in full on the date of grant. At the discretion of the
Administrator, the Company shall have a right of repurchase of Option Shares.
The Administrator shall have the discretion to specify the times at which such
right of repurchase shall lapse; provided, however, that



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the right of repurchase must lapse at the rate of at least 20% per year over
five years from the date the option was granted.

            (c)   Limitation on Other Grants. The Administrator shall have no
discretion to grant Options under this Plan other than as set forth in Sections
6(a) and 6(b).

            (d)   Nonassignability of Option Rights. No Option shall be
assignable or otherwise transferable by the Optionee, except by will or the laws
of descent and distribution. During the life of an Optionee, an Option shall be
exercisable only by the Optionee.

            (e)   Payment. Except as provided below, payment in full, in cash,
shall be made for all Option Shares purchased at the time written notice of
exercise of an Option is given to the Company, and proceeds of any payment shall
constitute general funds of the Company. Payment may also be made pursuant to a
cashless exercise/sale procedure. At the time an Option is granted or exercised,
the Administrator, in its absolute discretion, may authorize any one or more of
the following additional methods of payment: (i) acceptance of the Optionee's
full recourse promissory note for all or part of the Option price, less any par
value per share, which must be paid in cash, payable on such terms and bearing
such interest rate as determined by the Administrator (but in no event less than
the minimum interest rate specified under the Code at which no additional
interest on debt instruments of such type would be imputed), which promissory
note may be either secured or unsecured in such manner as the Administrator
shall approve (including, without limitation, by a security interest in the
Shares); (ii) delivery by the Optionee of Common Stock already owned by the
Optionee for all or part of the Option price, provided the Fair Market Value of
such Common Stock is equal on the date of exercise to the Option price, or such
portion thereof as the Optionee is authorized to pay by delivery of such stock;
provided, however, that if an Optionee has exercised any portion of any Option
granted by the Company by delivery of Common Stock, the Optionee may not, within
six months following such exercise, exercise any Option granted under this Plan
by delivery of Common Stock; and (iii) any other consideration and method of
payment to the extent permitted under the California Corporations Code.

            (f)   Termination as Director. Unless determined otherwise by the
Administrator in its absolute discretion, to the extent not already expired or
exercised, an Option shall terminate at the earlier of: (i) the expiration of
the term of the Option; or (ii) three months after the last day served by the
Optionee as a director of the Company; provided, that an Option shall be
exercisable after the date of termination of service as a director only to the
extent exercisable on the date of termination; and provided further,



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that if termination of service as a director is due to the Optionee's death or
"disability" (as determined in accordance with Section 22(e)(3) of the Code),
the Optionee, or the Optionee's personal representative (or any other person who
acquires the Option from the Optionee by will or the applicable laws of descent
and distribution), may at any time within 12 months after the termination of
service as a director (or such lesser period as is specified in the Option
Agreement but in no event after the expiration of the term of the Option),
exercise the rights to the extent they were exercisable on the date of the
termination.

            (g)   Withholding and Employment Taxes. At the time of exercise of
an Option (or at such later time(s) as the Administrator may prescribe), the
Optionee shall remit to the Company in cash all applicable federal and state
withholding and employment taxes. If authorized by the Administrator in its sole
discretion, an Optionee shall be permitted to elect, by means of a form of
election to be prescribed by the Administrator, to have shares of Common Stock
which are acquired upon exercise of the Option withheld by the Company or to
tender to the Company other shares of Common Stock or other securities of the
Company owned by the Optionee on the date of determination of the amount of tax
to be withheld as a result of the exercise of such Option (the "Tax Date") to
pay the amount of withholding taxes due. Any securities so withheld or tendered
shall be valued by the Company as of the Tax Date.

            (h)   Option Term. Each Option shall expire ten years after the date
of grant.

            (i)   Exercise Price. The exercise price of any Option granted to
any person who owns, directly or by attribution under the Code currently Section
424(d), stock possessing more than ten percent of the total combined voting
power of all classes of stock of the Company or of any Affiliate (a "Ten Percent
Stockholder") shall in no event be less than 110% of the fair market value
(determined in accordance with 2(i) of the stock covered by the Option at the
time the Option is granted.

      8.    MANNER OF EXERCISE

            (a)   An Optionee wishing to exercise an Option shall give written
notice to the Company at its principal executive office, to the attention of the
officer of the Company designated by the Administrator, accompanied by payment
of the exercise price as provided in Section 7(e) and, if required, by payment
of any federal or state withholding or employment taxes required to be withheld
due to exercise of the Option. The date the Company receives written notice of
an exercise accompanied by payment of the exercise price and any required
federal or state withholding or employment taxes will



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be considered as the date such Option was exercised. Unless otherwise provided
by the Administrator, Options may be exercised only twice in any calendar year.

            (b)   Promptly after the date an Option is exercised, the Company
shall, without stock issue or transfer taxes to the optionee or other person
entitled to exercise the Option, deliver to the Optionee or such other person a
certificate or certificates for the requisite number of shares of Common Stock.
An Optionee or transferee of an Optionee shall not have any privileges as a
stockholder with respect to any Common Stock covered by the Option until the
date of issuance of a stock certificate.

      9.    NO RIGHT TO DIRECTORSHIP

            Neither this Plan nor any Option shall confer upon any Optionee any
right with respect to continuation of the Optionee's membership on the Board or
shall interfere in any way with provisions in the Company's Certificate of
Incorporation, as amended, and Bylaws, as amended, relating to the election,
appointment, terms of office, and removal of members of the Board.

      10.   FINANCIAL INFORMATION

            The Company shall provide to each Optionee during the period the
Optionee holds an outstanding Option a copy of the financial statements of the
Company as prepared either by the Company or independent certified public
accountants of the Company. Such financial statements shall be delivered as soon
as practicable following the end of the Company's fiscal year during the period
Options are outstanding.

      11.   LEGAL REQUIREMENTS

            The Company shall not be obligated to offer or sell any Shares upon
exercise of any Option unless the Shares are at that time effectively registered
or exempt from registration under the federal securities laws and the offer and
sale of the Shares are otherwise in compliance with all applicable securities
laws and the regulations of any stock exchange on which the Company's securities
may then be listed. The Company shall have no obligation to register the Shares
covered by this Plan under the federal securities laws or take any other steps
as may be necessary to enable the Shares covered by this Plan to be offered and
sold under federal or other securities laws. Upon exercising all or any portion
of an Option, an Optionee may be required to furnish representations or
undertakings deemed appropriate by the Company to enable the offer and sale of
the Shares or subsequent transfers of any interest in the Shares to comply with
applicable securities laws. Certificates evidencing Shares acquired upon
exercise of Options shall



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bear any legend required by, or useful for purposes of compliance with,
applicable securities laws, this Plan or the Option Agreements.

      12.   AMENDMENTS TO PLAN

            The Board may amend this Plan at any time. Without the consent of an
optionee, no amendment may adversely affect outstanding Options. No amendment
shall require stockholder approval unless:

            (a)   stockholder approval is required to meet the exemptions
provided by Rule 16b-3, or any successor rule thereto or under applicable state
statutes; or

            (b)   the Board otherwise concludes that stockholder approval is
advisable.

      13.   STOCKHOLDER APPROVAL; TERM

            This Plan shall become effective upon adoption by the Board of
Directors; provided, however, that no Option shall be exercisable unless and
until written consent of holders of a majority of the outstanding shares of
capital stock of the Company, or approval by holders of a majority of shares of
capital stock of the Company present, or represented, and entitled to vote at a
validly called stockholders' meeting (or such greater number as may be required
by law or applicable governmental regulations or orders) is obtained within 12
months after adoption by the Board. This Plan shall terminate ten years after
adoption by the Board unless terminated earlier by the Board. The Board may
terminate this Plan at any time without stockholder approval. No Options shall
be granted after termination of this Plan, but termination shall not affect
rights and obligations under then-outstanding Options.



               Adopted by the Board of Directors:  March 17, 2000

               Approved by the Stockholders:  _______, 2000


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