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                                                                     EXHIBIT 5.1

                      [CONYERS DILL & PEARMAN LETTERHEAD]

22 January 2001

Marvell Technology Group Ltd
3rd Floor
Richmond House
12 Par-la-Ville Road
Hamilton HM DX
Bermuda


Dear Sirs

MARVELL TECHNOLOGY GROUP LTD - REGISTRATION STATEMENT ON FORM S-8 FOR 6,834,697
SHARES OF COMMON STOCK ISSUED PURSUANT TO ASSUMED OPTIONS OF GALILEO TECHNOLOGY
LTD.

We have acted as special legal counsel in Bermuda to Marvell Technology Group
Ltd., a Bermuda company (the "Company"). We have examined the Registration
Statement on Form S-8 (the "Registration Statement") to be filed by the Company
with the U.S. Securities and Exchange Commission in connection with the
registration under the U.S. Securities Act of 1933, as amended (the "Securities
Act"), of 6,834,697 shares of the Company's common stock at $0.002 par value
per share (the "Common Stock"), reserved for issuance under the Galileo
Technology Ltd. 1998 Non-Employee Directors Stock Option Plan, the Galileo
Technology Ltd. 1997 GTI Stock Option Plan and the Galileo Technology Ltd. 1997
Employees' Stock Option Plan (the "Assumed Plans,"), which were assumed by the
Company pursuant to the Agreement of Merger, dated as of 16 October 2000, among
the Company, Galileo Technology Ltd. and Toshack Acquisitions Ltd. (the "Merger
Agreement").

For the purposes of rendering this opinion, we have made such examinations as
we have deemed necessary under the circumstances and as part of such
examination, we have examined, among other things, originals and copies,
certified or otherwise identified to our satisfaction, of such documents,
corporate records and other instruments as we have deemed necessary or
appropriate. For the purposes of such examination, we have assumed the
genuineness of all signatures on original documents and the conformity to
original documents of all copies submitted to us.

On the basis of and in reliance upon the foregoing, we are of the opinion that,
assuming the Registration Statement shall have become effective pursuant to the
provisions of the Securities Act, the shares of Common Stock being offered
under the Assumed Plans, when issued and paid for in accordance with the
provisions of the Assumed Plans, will be validly issued, fully paid and
non-assessable (meaning that no further sums are required to be paid by the
holders thereof in connection with the issue thereof).
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We have made no investigation of and express no opinion in relation to the laws
of any jurisdiction, other than Bermuda. This opinion is to be governed by and
construed in accordance with the laws of Bermuda and is limited to and is given
on the basis of the current law and practice in Bermuda.

We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement. In giving such consent, we do not thereby admit that we
are in the category of persons whose consent is required under Section 7 of the
Securities act.

Yours faithfully

/s/ CONYERS DILL & PEARMAN
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    CONYERS DILL & PEARMAN