Maf, the X-fi sounds much better than the Audigy 2. Everything is just clearer. I don't know about performance differences but Drinky told me that you free up more CPU power with a X-FI. Also, the X-Fi supports more sound effects and more importantly, it works much better for Vista if you want to continue using EAX.
1000W power supply.
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Do you have it running 24/7 too?
My PC used to be always on but now I try to turn it off more often. Does how much power the PC's actually using make any difference? I know that the CPU and GPUS draw much less power when you're not gaming but does it make any difference in terms of electricity that is being used? Electricity is ridiculously expensive in California because of that idiot Gray Davis.