GTX 550 Ti SLI Scaling Review & Value Analysis Linus Tech Tips - YouTube
Computer Build 2012 - Update - Installing SLI Graphics or Video Cards GTX 550 Ti - YouTube
GIGABYTE GV-N550OC-1GI GeForce GTX 550 Ti Video Card - 1GB, GDDR5, PCI-Express 2.0 (x16), Mini HDMI, Dual DVI, DirectX 11, SLI Ready, Overclocked at TigerDirect.com
Amazon.com: ASUS GeForce GTX 550 Ti (Fermi) 1GB 192-bit GDDR5 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card, ENGTX550 TI DC TOP/DI/1GD5 : Electronics