No sound

I have no sound on my laptop and I am getting "No audio device installed" message, I would be very glad of any suggestions to put this right
I Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft® Windows Vista™ Home Premium, Service Pack 2, 32 bit
Processor: AMD Turion(tm) 64 X2 Mobile Technology TL-58, x64 Family 15 Model 104 Stepping 1
Processor Count: 2
RAM: 1982 Mb
Graphics Card: NVIDIA GeForce 7150M / nForce 630M, 64 Mb
Hard Drives: C: Total - 106548 MB, Free - 11705 MB; D: Total - 7922 MB, Free - 4 MB;
Motherboard: Quanta, 30CF
Antivirus: Norton Internet Security, Updated and Enabledhave a Compaq laptop operating Windows Vista