Power Mac G5 2.3ghz Dual Core or Refurb iMac 24-inch 2.93GHz Intel 2 duo

I have a $1200 budget and I need something powerful to edit photos. I load about 2000 photos into Adobe Bridge at a time and need something SUPER FAST to get these done quickly plus run Photoshop CS4 super fast. The choices are a Power Mac G5 2.3ghz Dual Core 8.2GB RAM from Powermax.com or a Refurbished iMac 24-inch 2.93GHz Intel Core 2 duo 4GB RAM straight from Apple. Bare bones, I need to know what will run faster, not connected to internet, no extra programs but Photoshop CS4, Bridge and an Image Viewer like Xee. I have imac g5 and macbook for personal use. This will be strictly work. I shoot weddings and sports which are averaging 4000 a shoot and need the fastest computer with my budget. Thanks!