Exhibit 4.5



DOT HILL SYSTEMS CORP.        WARRANT TO PURCHASE SHARES OF COMMON STOCK

THIS CERTIFIES THAT, for value received, SUN MICROSYSTEMS, INC. and its assigns are entitled to subscribe for and purchase 1,239,527shares of the fully
paid and nonassessable Common Stock (as adjusted pursuant to Section 4 hereof, the "Shares") of Dot Hill Systems Corp., a Delaware corporation (the "Company"), at the price of $2.97 per share,
the average of the Company's closing price as reported by the New York Stock Exchange 60 trading days before the Date of Grant (such price and such other price as shall result, from time to time, from
the adjustments specified in Section 4 hereof is herein referred to as the "Warrant Price"), subject to the provisions and upon the terms and conditions hereinafter set forth. As used herein,
the term "Date of Grant" shall mean the date set forth underneath the Company's signature hereto, and (b) the term "Other Warrants" shall mean any other warrants issued by the Company in
connection with the transaction with respect to which this Warrant was issued, and any warrant issued upon transfer or partial exercise of this Warrant. The term "Warrant" as used herein shall be
deemed to include Other Warrants unless the context clearly requires otherwise.

1.Exercisability; Term.Subject to Section 10.1 below, the purchase right represented by this Warrant is
exercisable as to 413,175 shares immediately, and an additional 413,176 shares on each of the first anniversary and second anniversary of the Date of Grant, in whole or in part, at any time and from
time to time from the Date of Grant through Five (5) years after the Date of Grant.

2.Method of Exercise; Payment; Issuance of New Warrant.Subject to Section 1 hereof, the purchase right
represented by this Warrant may be exercised by the holder hereof, in whole or in part and from time to time, at the election of the holder hereof, by (a) the surrender of this Warrant (with
the notice of exercise substantially in the form attached hereto as Exhibit A-1 duly completed and executed) at the principal office of the Company and by the payment to the
Company, by certified or bank check, or by wire transfer to an account designated by the Company (a "Wire Transfer") of an amount equal to the then applicable Warrant Price multiplied by the number of
Shares then being purchased, or (b) if in connection with a registered public offering of the Company's securities, the surrender of this Warrant (with the notice of exercise form attached
hereto as Exhibit A-2 duly completed and executed) at the principal office of the Company together with notice of arrangements reasonably satisfactory to the Company for payment to
the Company either by certified or bank check or by Wire Transfer from the proceeds of the sale of shares to be sold by the holder in such public offering of an amount equal to the then applicable
Warrant Price per share multiplied by the number of Shares then being purchased or (c) exercise of the "net issuance" right provided for in Section 10.2 hereof. The person or persons in
whose name(s) any certificate(s) representing the Shares shall be issuable upon exercise of this Warrant shall be deemed to have become the holder(s) of record of, and shall be treated for all
purposes as the record holder(s) of, the shares represented thereby (and such shares shall be deemed to have been issued) immediately prior to the close of business on the date or dates upon which
this Warrant is exercised. In the event of any exercise of the rights represented by this Warrant, certificates for the shares of stock so purchased shall be delivered to the holder hereof as soon as
practicable and, if requested by the holder of this Warrant, the Company shall cause its transfer agent to deliver the certificate representing Shares issued upon exercise of this Warrant to a broker
or

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other person (as directed by the holder exercising this Warrant) within the time period required to settle any trade made by the holder after exercise of this Warrant.

3.Stock Fully Paid; Reservation of Shares.All Shares that may be issued upon the exercise of the rights
represented by this Warrant will, upon issuance pursuant to the terms and conditions herein, be fully paid and nonassessable, and free from all taxes, liens and charges with respect to the issue
thereof. During the period within which the rights represented by this Warrant may be exercised, the Company will at all times have authorized, and reserved for the purpose of the issue upon exercise
of the purchase rights evidenced by this Warrant, a sufficient number of shares of its Common Stock to provide for the exercise of the rights represented by this Warrant.

4.Adjustment of Warrant Price and Number of Shares.The number and kind of securities purchasable upon the
exercise of this Warrant and the Warrant Price shall be subject to adjustment from time to time upon the occurrence of certain events, as follows:



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5.Notice of Adjustments.Whenever the Warrant Price or the number of Shares purchasable hereunder shall be
adjusted pursuant to Section 4 hereof, the Company shall make a certificate signed by its chief financial officer setting forth, in reasonable detail, the event requiring the adjustment, the
amount of the adjustment, the method by which such adjustment was calculated, and the Warrant Price and the number of Shares purchasable hereunder after giving effect to such adjustment, and shall
cause copies of such certificate to be mailed (without regard to Section 13 hereof, by first class mail, postage prepaid) to the holder of this Warrant at such holder's last known address.

6.Fractional Shares.No fractional shares of Common Stock will be issued in connection with any exercise
hereunder, but in lieu of such fractional shares the Company shall make a cash payment therefor based on the fair market value of the Common Stock on the date of exercise as reasonably determined in
good faith by the Company's Board of Directors.

7.Compliance with Securities Act; Disposition of Warrant or Shares of Common Stock.



Said
legend shall be removed by the Company, upon the request of a holder, at such time as the restrictions on the transfer of the applicable security shall have terminated. In addition,
in connection

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with the issuance of this Warrant, the holder specifically represents to the Company by acceptance of this Warrant as follows:



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8.Rights as Shareholders; Information.No holder of this Warrant, as such, shall be entitled to vote or receive
dividends or be deemed the holder of Common Stock or any other securities which may at any time be issuable upon the exercise hereof for any purpose, nor shall anything contained herein be construed
to confer upon the holder of this Warrant, as such, any of the rights of a shareholder of the Company or any right to vote for the election of directors or upon any matter submitted to shareholders at
any meeting thereof, or to receive notice of meetings, or to receive dividends or subscription rights or otherwise until this Warrant shall have been exercised and the Shares purchasable upon the
exercise hereof shall have become deliverable, as provided herein. Notwithstanding the foregoing, the Company will transmit to the holder of this Warrant such information, documents and reports as are
generally distributed to the holders of any class or series of the securities of the Company concurrently with the distribution thereof to the shareholders.

9.Registration Rights.



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9.Additional Rights.

10.1Mergers.The Company shall provide the holder of this Warrant with at least twenty (20) days'
written notice prior to the closing thereof of the terms and conditions of any of the following transactions (an "Acquisition"): (i) the sale, lease, exchange, conveyance or other disposition
of all or substantially all of the Company's property or business, or (ii) its merger into or consolidation with any other corporation (other than a wholly-owned subsidiary of the Company), or
any transaction (including a merger or other reorganization) or series of related transactions, in which more than 50% of the voting power of the Company is disposed of. In the event of an
Acquisition, the purchase rights represented by this Warrant shall be fully exercisable.

10.2Right to Convert Warrant into Stock: Net Issuance.



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X =
B - AY


Where:

X =

the number of shares of Common Stock that may be issued to the holderY =

the fair market value of one share of Common StockA =

the aggregate Warrant Price of the specified number of Converted Warrant Shares immediately prior to the exercise of the Conversion Right (i.e.,the number of Converted Warrant Sharesmultiplied bythe Warrant Price)B =

the aggregate fair market value of the specified number of converted Warrant Shares (i.e., the number of Converted Warrant Sharesmultiplied bythe fair
market value of one Converted Warrant Shares)


No fractional shares shall be issuable upon exercise of the Conversion Right, and, if the number of shares to be issued determined in accordance with the
foregoing formula is other than a whole number, the Company shall pay to the holder an amount in cash equal to the fair market value of the resulting fractional share on the Conversion Date (as
hereinafter defined). For purposes of Section 9 of this Warrant, shares issued pursuant to the Conversion Right shall be treated as if they were issued upon the exercise of this Warrant.



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If
closing prices or closing bid prices are no longer reported by a securities exchange or other trading system, the closing price or closing bid price shall be that which is reported by such
securities exchange or other trading system at 4:00 p.m. New York City time on the applicable trading day.

10.3Exercise Prior to Expiration.To the extent this Warrant is not previously exercised as to all of the
Shares subject hereto, and if the fair market value of one share of the Common Stock is greater than the Warrant Price then in effect, this Warrant shall be deemed automatically exercised pursuant to
Section 10.2 above (even if not surrendered) immediately before its expiration. For purposes of such automatic exercise, the fair market value of one share of the Series Preferred upon such
expiration shall be determined pursuant to Section 10.2(c). To the extent this Warrant or any portion thereof is deemed automatically exercised pursuant to this Section 10.3, the Company
agrees to promptly notify the holder hereof of the number of Shares, if any, the holder hereof is to receive by reason of such automatic exercise.

10.Representations and Warranties.The Company represents and warrants to the holder of this Warrant as
follows:



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11.Modification and Waiver.This Warrant and any provision hereof may be changed, waived, discharged or
terminated only by an instrument in writing signed by the party against which enforcement of the same is sought.

12.Notices.Any notice, request, communication or other document required or permitted to be given or delivered
to the holder hereof or the Company shall be delivered, or shall be sent by certified or registered mail, postage prepaid, to each such holder at its address as shown on the books of the Company or to
the Company at the address indicated therefor on the signature page of this Warrant.

13.Binding Effect on Successors.This Warrant shall be binding upon any corporation succeeding the Company by
merger, consolidation or acquisition of all or substantially all of the Company's assets, and all of the obligations of the Company relating to the Shares issuable upon the exercise or conversion of
this Warrant shall survive the exercise, conversion and termination of this Warrant and all of the covenants and agreements of the Company shall inure to the benefit of the successors and assigns of
the holder hereof.

14.Lost Warrants or Stock Certificates.The Company covenants to the holder hereof that, upon receipt of
evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this Warrant or any stock certificate and, in the case of any such loss, theft or destruction, upon
receipt of an indemnity reasonably satisfactory to the Company, or in the case of any such mutilation upon surrender and cancellation of such Warrant or stock certificate, the Company will make and
deliver a new Warrant or stock certificate, of like tenor, in lieu of the lost, stolen, destroyed or mutilated Warrant or stock certificate.

15.Descriptive Headings.The descriptive headings of the several paragraphs of this Warrant are inserted for
convenience only and do not constitute a part of this Warrant. The language in this Warrant shall be construed as to its fair meaning without regard to which party drafted this Warrant.

16.Governing Law.This Warrant shall be construed and enforced in accordance with, and the rights of the
parties shall be governed by, the laws of the State of California.

17.Survival of Representations, Warranties and Agreements.All representations and warranties of the Company
and the holder hereof contained herein shall survive the Date of Grant, the exercise or conversion of this Warrant (or any part hereof) or the termination or expiration of rights hereunder. All
agreements of the Company and the holder hereof contained herein shall survive indefinitely until, by their respective terms, they are no longer operative.

18.Remedies.In case any one or more of the covenants and agreements contained in this Warrant shall have been
breached, the holders hereof (in the case of a breach by the Company), or the Company (in the case of a breach by a holder), may proceed to protect and enforce their or its rights either by suit in
equity and/or by action at law, including, but not limited to, an action for damages as a result of any such breach and/or an action for specific performance of any such covenant or agreement
contained in this Warrant.

19.No Impairment of Rights.The Company will not, by amendment of its Charter or through any other means, avoid
or seek to avoid the observance or performance of any of the terms of this Warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such
action as may be necessary or appropriate in order to protect the rights of the holder of this Warrant against impairment.

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20.Severability.The invalidity or unenforceability of any provision of this Warrant in any jurisdiction shall
not affect the validity or enforceability of such provision in any other jurisdiction, or affect any other provision of this Warrant, which shall remain in full force and effect.

21.Recovery of Litigation Costs.If any legal action or other proceeding is brought for the enforcement of this
Warrant, or because of an alleged dispute, breach, default, or misrepresentation in connection with any of the provisions of this Warrant, the successful or prevailing party or parties shall be
entitled to recover reasonable attorneys' fees and other costs incurred in that action or proceeding, in addition to any other relief to which it or they may be entitled.

[Remainder of page intentionally left blank]

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22.Entire Agreement; Modification.This Warrant constitutes the entire agreement between the parties pertaining
to the subject matter contained in it and supersedes all prior and contemporaneous agreements, representations, and undertakings of the parties, whether oral or written, with respect to such subject
matter.

| |  | DOT HILL SYSTEMS CORP.                     
| |  | -------------------------------------------
| |  | /s/ JAMES L. LAMBERT                       
| |  | By: James L. Lambert                       
| |  | Title:Chief Executive Officer and President
| |  | Address:                                   
| |  |                                            
| |  | Date: May 24, 2002                         

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EXHIBIT A-1        NOTICE OF EXERCISE

To: DOT HILL SYSTEMS CORP. (the "Company")

1.    The
undersigned hereby:



2.    Please
issue a certificate or certificates representing said shares in the name of the undersigned or in such other name or names as are specified below:

| |  | (Name)    |  | 
| |  | --------- |  | 
| |  |           |  | 
| |  |           |  | 
| |  |           |  | 
| |  | (Address) |  | 

3.    The
undersigned represents that the aforesaid shares are being acquired for the account of the undersigned for investment and not with a view to, or for resale in
connection with, the distribution thereof and that the undersigned has no present intention of distributing or reselling such shares, all except as in compliance with applicable securities laws.

|       |  | SUN MICROSYSTEMS, INC.
|------ |  | ----------------------
|       |  |                       
|       |  | (Signature)           
|(Date) |  |                       

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EXHIBIT A-2        NOTICE OF EXERCISE

To: DOT HILL SYSTEMS CORP. (the "Company")

1.    Contingent
upon and effective immediately prior to the closing (the "Closing") of the Company's public offering contemplated by the Registration Statement on
Form S, filed, 19, the undersigned hereby:



2.    Please
deliver to the custodian for the selling shareholders a stock certificate representing such shares.

3.    The
undersigned has instructed the custodian for the selling shareholders to deliver to the Company $                        or, if
less, the net proceeds due the undersigned
from the sale of shares in the aforesaid public offering. If such net proceeds are less than the purchase price for such shares, the undersigned agrees to deliver the difference to the Company prior
to the Closing.

|       |  | SUN MICROSYSTEMS, INC. |  | 
|------ |  | ---------------------- |  | 
|       |  |                        |  | 
|       |  | (Name)                 |  | 
|       |  |                        |  | 
|       |  |                        |  | 
|       |  |                        |  | 
|       |  | (Address)              |  | 
|(Date) |  |                        |  | 

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EXHIBIT B        CHARTER

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