[Brians256]

OK, quick project planning.

First, your objectives:
- Make machine quieter
- Use existing computer parts
- Upgrade cooling

Next, we see what is your problem:
- Too loud
- Key fact: GPU fan is causing most of the noise when it is fully loaded

Possible suggested solutions:
- Water cooling
- Change type of aircooling

I would recommend you look at changing your air cooling at this point. Unless you are planning to do some extreme overclocking, the current air-cooling solutions are really quite good. Your real problem is that you have some low-end cooling components.

Recommendations:
- Replace cooling on your GPU card with 3rd party "VGA" cooler (NV Silencer 5 Rev 3 if you slice off some plastic might work, or the Zalman VF900 works well)
- Use fan control to make the new GPU cooler's fan quiet enough for you
- Think about removing one of your 120mm fans and/or using Yate-Loon fans at lower than 12 volts
- Think about using a Scythe Ninja heatsink right by the 120mm exhaust fan below