Amazon.com: ASUS GeForce GTX TITAN 6GB 384-bit GDDR5 PCI Express 3.0 SLI Support Video Card GTXTITAN-6GD5 : Electronics
ASUS GTXTITANZ-12GD5 G-SYNC Support GeForce GTX TITAN Z 12GB 768-Bit GDDR5 PCI Express 3.0 HDCP Ready SLI Support Video Card GPUs / Video Graphics Cards - Newegg.com