Slightly tinkered with my Fujitsu P5730 workstation today.
Bought a Radeon HD 6850 with Accelero Twin Turbo II cooler for 50â‚¬. Since there was no way of fitting the huge GPU cooler next to the large CPU heatsink, I decided to toss the original fans and just zip-tie a 120mm one on instead. I also had to cut a bit from the fins, since they were making contact with the screws of CPU heatsink.
The stock 300W power supply also didn't have a PCI-E 6pin connector, so I had to mod my way around that. I took a spare PCI-E wire of unknown modular power supply, cut it apart and soldered the three yellows and blacks together. After that I ripped apart one of the S-ATA power connectors, soldered my wires there to the 12v line and reassembled the connector.
300W PSU might sound too small for this kind of setup, but the load test confirmed my calculations: It's close, but it's still sufficient since the computer won't crash even under full load.
The temperatures on Furmark & Orthos load were around 50'c for CPU and 78'c for GPU. The noise level is almost inaudible and in this case the loudest sound from the computer is the slight humm of HDD spinning.
Intel E7500 (Max TDP 65W)
HD 6850 1GB (Max TDP around 140W)