Sound Card Problem

Hi everyone out there! I don't know why I have so much problems with my computer. Is it too old? I built my computer back in 2004. Windows XP Pro SP1, 1GB of RAM, 300GB HDD (new), 1.5GHz (AMD), and Audiogy 2 ZS. It ran well except in August one of my HDDs didn't work and I took it out. Now I have another problem when I installed SP2. I don't have any more sound. I checked my Audio Properties and it show me that I don't sound card installed! But do I have 2 sound cards (Audiogy 2 ZS, M-Audio 1010LT) installed in my computer, none of them have a conflict. Why my computer didn't detect my sound cards anymore? I reinstalled both sound cards and drivers but my computer still didn't detect my sound cards. I tried installed only 1 sound card but still not detect. So I reformated my computer and installed everything from scratch but I still have a same issue when I installed SP2. Does anyone know what's wrong with SP2 and didn't detect my sound cards? Any help will be appreciated... thanks.