Exhibit 21.1

SILICON GRAPHICS, INC. SUBSIDIARIES

|Name                                          |  | Jurisdiction of
Incorporation
|--------------------------------------------- |  | -----------------------------
|Alias/Wavefront, Inc.                         |  | California                   
|ParaGraph International, Inc.                 |  | California                   
|WTI Developments, Inc.                        |  | California                   
|Cray Research, LLC                            |  | Delaware                     
|Cray Asia/Pacific, Inc.                       |  | Delaware                     
|Cray Financial Corporation                    |  | Delaware                     
|Cray Research (America Latina) Ltd.           |  | Delaware                     
|Cray Research (Eastern Europe) Ltd.           |  | Delaware                     
|Cray Research (India) Ltd.                    |  | Delaware                     
|Cray Research International, Inc.             |  | Delaware                     
|Silicon Graphics Federal, Inc.                |  | Delaware                     
|Silicon Graphics Real Estate, Inc.            |  | Delaware                     
|Silicon Graphics World Trade Corporation      |  | Delaware                     
|Silicon Studio, Inc.                          |  | Delaware                     
|Silicon Graphics S.A.                         |  | Argentina                    
|Silicon Graphics Pty Limited                  |  | Australia                    
|Silicon Graphics International Inc.           |  | Barbados                     
|Silicon Graphics S.A./N.V.                    |  | Belgium                      
|Alias/Wavefront N.V.                          |  | Belgium                      
|Silicon Graphics Comercio e Serviços Limitada |  | Brazil                       
|Cray Research (Canada) Inc.                   |  | Canada                       
|Silicon Graphics Limited                      |  | Canada                       
|Wavefront Canada Limited                      |  | Canada                       
|Silicon Graphics spolecnost rucerum omezenym  |  | Czech Republic               
|Silicon Graphics A/S                          |  | Denmark                      
|Silicon Graphics                              |  | France                       
|Alias/Wavefront SAS                           |  | France                       
|Silicon Graphics GmbH                         |  | Germany                      
|Alias/Wavefront GmbH                          |  | Germany                      
|Silicon Graphics Limited                      |  | Hong Kong                    
|Silicon Graphics Kft.                         |  | Hungary                      
|Silicon Graphics Systems (India) Ltd          |  | India                        
|Cray Research (Israel) Ltd.                   |  | Israel                       
|Silicon Graphics Computer Systems Limited     |  | Israel                       
|Alias/Wavefront Srl.                          |  | Italy                        
|Silicon Graphics S.p.A.                       |  | Italy                        
|Alias/Wavefront KK                            |  | Japan                        
|SGI Japan Limited.                            |  | Japan                        
|Korea Silicon Graphics Ltd.                   |  | South Korea                  
|Silicon Graphics Sdn. Bhd.                    |  | Malaysia                     
|Silicon Graphics S.A. de C.V.                 |  | Mexico                       
|Silicon Graphics B.V.                         |  | Netherlands                  
|Silicon Graphics Europe Trade B.V.            |  | Netherlands                  
|Silicon Graphics World Trade B.V.             |  | Netherlands                  
|Silicon Graphics Limited                      |  | New Zealand                  
|Silicon Graphics A/S                          |  | Norway                       

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|Silicon Graphics Computer Engineering and Technology (China) Co. Ltd. |  | People's Republic of China
|--------------------------------------------------------------------- |  | --------------------------
|Silicon Graphics Pte. Limited                                         |  | Singapore                 
|Silicon Graphics (Pty) Limited                                        |  | South Africa              
|Silicon Graphics, S.A.                                                |  | Spain                     
|Silicon Graphics AB                                                   |  | Sweden                    
|Silicon Graphics S.A.                                                 |  | Switzerland               
|Silicon Graphics Manufacturing S.A.                                   |  | Switzerland               
|Silicon Graphics Trading SARL                                         |  | Switzerland               
|Silicon Graphics Limited                                              |  | Taiwan                    
|Silicon Graphics Bilbisayar Sistemleri Anonim Siket                   |  | Turkey                    
|Alias/Wavefront Limited                                               |  | United Kingdom            
|Silicon Graphics Limited                                              |  | United Kingdom            
|Silicon Graphics Manufacturing Finance Limited                        |  | Jersey Channel Islands    
|Silicon Graphics S.A.                                                 |  | Venezuela                 

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