PRESS RELEASE DATED APRIL 21, 1999

Exhibit 99

[LETTERHEAD AND LOGO OF AMD]


CONTACTS:

Steve Skaggs
Senior Vice President and Chief Financial
Officer

Roddy Sloss
Vice President Finance
Lattice Semiconductor Corporation
503/268-8000

Scott Allen
Director of Public Relations
Advanced Micro Devices
408/749-3311

LATTICE SEMICONDUCTOR ACQUIRES VANTIS CORPORATION FROM AMD

SUNNYVALE, CA - APRIL 21, 1999 - Lattice Semiconductor Corporation (NASDAQ:
LSCC) and Advanced Micro Devices (NYSE: AMD) today announced a definitive
agreement pursuant to which Lattice Semiconductor will acquire Vantis
Corporation, the wholly owned programmable logic subsidiary of AMD, for $500
million in cash. The acquisition price includes the assumption of Vantis' net
cash and cash equivalents, which are expected to be approximately $60 million at
closing. The acquisition will be financed through a combination of cash on hand,
bank borrowings and other sources of financing. AMD and Lattice Semiconductor
will make a mutual 338(h)10 tax election that will allow acquisition-related
goodwill to be tax deductible for Lattice.

Lattice and AMD anticipate completing the deal before the end of Lattice's
second fiscal quarter ending September 1999. The transaction will be accounted
for as a purchase. While the transaction will be initially dilutive to Lattice's
earnings per share, Lattice expects it to be accretive to the company's cash
earnings in calendar 2000. Upon completion of the transaction, Vantis
Corporation will be a wholly owned subsidiary of Lattice. Based on proforma
financial results for calendar 1998, the combined revenues of Lattice and Vantis
would have been approximately $400 million.

"This is clearly a major strategic move for Lattice," stated Cyrus Y. Tsui,
Lattice president and chief executive officer. "With significantly expanded R&D
and sales organizations, we will now be able to increase new product development
efforts and deliver innovative, higher density programmable solutions to
customers sooner. As a result, we will become a stronger and more viable
competitor and offer a broader range of programmable devices."

Rich Previte, AMD president and Vantis chairman, said, "We are pleased that the
successful Vantis organization will now join a strong Lattice team. The
divestiture of Vantis strengthens our balance sheet and allows AMD to focus its
investment and resources on its core businesses, which consist of
microprocessors and other circuits that enhance the value of personal computers
as communications and information processing tools. AMD's best opportunities for
profitable growth lie in offering products that provide

improved connectivity, a superior visual computing platform, and better Internet
access from personal computers."

"The acquisition merges two organizations with long and distinguished histories
of innovation," stated Tsui. "We will have a critical mass of talent, products
and resources which can more effectively meet the rapidly changing needs of
customers. Initially, the combination of our recently released BFW products and
Vantis's 3.3 volt MACH(R) products will offer customers the broadest choice of
high performance programmable devices. We are anxious to utilize the deep
technical talent pool and broad intellectual property portfolio of the combined
company to develop and deliver our next generation products to our complimentary
customer base.

"Lattice has demonstrated a consistent track record of innovation, competitive
success and strong financial performance. This combination provides an
opportunity to streamline our operations, increase our manufacturing volume, and
lower our overall cost structure. The addition of Vantis gives us a unique
opportunity to build a successful business by creating significant value for our
customers, and reward our shareholders and employees for a job well done," Tsui
concluded.

NOTE: Lattice Semiconductor will host a teleconference on Thursday, April 22, at
5:30 a.m. (PDT) to discuss the details of this transaction with securities
analysts.

Morgan Stanley Dean Witter served as financial advisor to Lattice in this
transaction. Broadview Associates has provided a fairness opinion to Lattice,
and Morgan Stanley Dean Witter and Donaldson Lufkin & Jenrette served as
financial advisors to AMD.


About Lattice Semiconductor Corporation
Lattice Semiconductor Corporation designs, develops and markets high performance
programmable logic devices ("PLDs") and related development system software.
Lattice is the inventor and world's leading supplier of in-system programmable
("ISPTM") PLDs. PLDs are standard semiconductor components that can be
configured by the end customer as specific logic functions, enabling shorter
design cycle times and reduced development costs. Lattice products are sold
worldwide through an extensive network of independent sales representatives and
distributors, primarily to original equipment manufacturers ("OEMs") of
communications, computing, industrial controls and military systems. Lattice was
founded in 1983 and is based in Hillsboro, Oregon.

About AMD
AMD is a global supplier of integrated circuits for the personal and networked
computer and communications markets. AMD produces processors, flash memories,
programmable logic devices, and products for communications and networking
applications. Founded in 1969 and based in Sunnyvale, California, AMD had
revenues of $2.5 billion in 1998.

Lattice headquarters are located at 5555 NE Moore Court, Hillsboro, Oregon 97124
USA; Telephone 503/268-8000; FAX 503/268-8037. For more information on Lattice
Semiconductor, access our World Wide Web site at http://www.latticesemi.com.
--------------------------

Additional information about Vantis Corporation is available at
http://www.vantis.com. AMD headquarters are located at One AMD Place, P.O.Box
- ---------------------
3453, Sunnyvale, California 94088 USA; Telephone 408/732-2400. Additional
information about AMD is available at http://www.amd.com.
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Safe Harbor Notice
Statements in this news release looking forward in time are made pursuant to the
safe harbor provisions of the Private Securities Litigation Reform Act of 1995.
Investors are cautioned that forward-looking statements involve risks and
uncertainties, including the effect of changing economic conditions, the effect
of overall semiconductor market conditions, product demand and market acceptance
risks, risks associated with dependencies on silicon wafer suppliers, the impact
of competitive products and pricing, technological and product development risks
and other risk factors detailed in the Company's Securities and Exchange
Commission filings. Actual results may differ materially from forward-looking
statements.


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Lattice Semiconductor, L (stylized) Lattice and isp, are either registered
trademarks or trademarks of Lattice Semiconductor Corporation in the United
States and/or other countries.
AMD is a trademark of Advanced Micro Devices, Inc.
Vantis is a trademark of Vantis Corporation. MACH is a registered trademark of
Vantis Corporation. Other marks are the property of their respective holders.