PCI Sound card for P4 system

I want to buy a pci sound card for my P4 dualcore system. Seems that the onboard sound is not working.
Here is the config
MB: ECS P4M800Pro v1.0A
CPU: P4 Dual core
RAM: Transcend 1GB 533
OS: Windows 7

i want to buy a cheaper card as this system is for more experiments and it is going to use by my 3year old kid to run the pre school interactive DVDs.

So i saw there are zebronics and intex is having cheaper 5.1 cards within Rs300.Also i saw some USB sound cards for rs100 in ebay.
Suggest me a good one within this price range. Apart from zebronics and intex, is there any? Is it worth buying the USB one?

Thanks,
Mani

Hello you can go with the Asus Xonar DG which is best sound card according to me. dont make use of USB sound cards it give you more problem. and even as you want the cheaper sound card so i will suggest you to go with the intex rather than zebronics its more better than it. but still compensate some more and buy the good one like i suggest Asus Xonar DG. its best.