Go here Realtek and download & install AC'97 Audio Codecs (Software). If they don't work, download & install High Definition Audio Codecs (Software) instead.
My Computer
At a glance
Windows 7 Ultimate 64-BitCore i7-990X Extreme Edition24 GB DDR3-1066 Hex-KitXFX HD5970 Black Edition Limited 4096MB
Computer type
PC/Desktop
Computer Manufacturer/Model Number
Custom build
OS
Windows 7 Ultimate 64-Bit
CPU
Core i7-990X Extreme Edition
Motherboard
ASUS P6T6 WS Revolution
Memory
24 GB DDR3-1066 Hex-Kit
Graphics Card(s)
XFX HD5970 Black Edition Limited 4096MB
Sound Card
Sound Blaster X-FI Titanium HD SB1270
Monitor(s) Displays
[will update soon]
Screen Resolution
[will update soon]
Hard Drives
OCZ SSD 60GB
Seagate 1TB
Samsung 1TB
Western Digital 1TB
LaCie 500GB
Go here Realtek and download & install AC'97 Audio Codecs (Software). If they don't work, download & install High Definition Audio Codecs (Software) instead.
They won't work. If you had clicked the link to that card it quite clearly says that it has the C-Media CMI8738 chip on it, not Realtek.
In all likelihood you're probably asking a lot from a sound card that was first made somewhere close to ten years ago, and at best has limited (if any) Windows 7 support. Looking at what passes for the Tech-Com download page, they don't even have Vista drivers for that card.
C-Media did release a Vista driver and a beta driver for Windows 7 for it,