Exhibit 21.1

SILICON GRAPHICS, INC. SUBSIDIARIES

|Name                                                                  |  | Jurisdiction of
Incorporation
|--------------------------------------------------------------------- |  | -----------------------------
|Alias Systems 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 S.A./N.V.                                            |  | Belgium                      
|Silicon Graphics Comercio e Serviços Limitada                         |  | Brazil                       
|Cray Research (Canada) Inc.                                           |  | Canada                       
|Silicon Graphics Limited                                              |  | Canada                       
|Silicon Graphics spolecnost rucerum omezenym                          |  | Czech Republic               
|Silicon Graphics A/S                                                  |  | Denmark                      
|Silicon Graphics                                                      |  | France                       
|Alias Systems SAS                                                     |  | France                       
|Silicon Graphics GmbH                                                 |  | Germany                      
|Alias Systems GmbH                                                    |  | Germany                      
|Silicon Graphics Limited                                              |  | Hong Kong                    
|Silicon Graphics Systems (India) Ltd                                  |  | India                        
|Cray Research (Israel) Ltd.                                           |  | Israel                       
|Silicon Graphics Computer Systems Limited                             |  | Israel                       
|Alias Systems Srl.                                                    |  | Italy                        
|Silicon Graphics S.p.A.                                               |  | Italy                        
|Alias Systems K.K.                                                    |  | 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                       
|Silicon Graphics Computer Engineering and Technology (China) Co. Ltd. |  | People's Republic of China   
|Silicon Graphics Pte. Limited                                         |  | Singapore                    
|Silicon Graphics                                                      |  | Spain                        
|Silicon Graphics AB                                                   |  | Sweden                       
|Silicon Graphics S.A.                                                 |  | Switzerland                  
|Silicon Graphics Finance S.A.                                         |  | Switzerland                  
|Silicon Graphics Trading SARL                                         |  | Switzerland                  
|Silicon Graphics Limited                                              |  | Taiwan                       
|Silicon Graphics Bilbisayar Sistemleri Anonim Siket                   |  | Turkey                       
|Alias Systems 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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