Hi, Here are BIOS ROM for any one who want to try the down clock and down volts HD 7970s. Even if you only want to put one HD 7970 in your Mac Pro, the noise level is reduced as stated in the other thread. As long as you have reference design HD 7970, one fan. Here are your bios. Features: -MAC OS boot screen. -0.956V at load -GPU clock 925Mhz -Memory Clock 1300 Mhz -less than 200 Watt consumption (~185W) Please update to the forum your BruceX performance in sec, as well as Sala LUXMARK, GPU score, and GPU+CPU score. Mine is 2x3.46G cpu, 128GB RAM, dual HD 7970 (2xD700s). Final cut Pro 10.1.1 BruceX performace: 23-24 sec. LUXMARK, GPU only 4,120. LUXMARK, CPU +GPU 5,146. Just for a comparison, my single GTX 680 BruceX is very poor at around 1:45. LUXMARK GPU score give me under 700. So OpenCL wise, AMD is several times outperforming and is also strongly supported by APPLE in its video editing products. Plus, now Adobe supports OPENCL in Premier Pro too. So please update yours. Note: g095vmac.rom was for my Gigabyte HD7970, X095vmac.rom was for my XFX HD7970, both are reference design. I think you can use either one if you are sure it's reference design cards. Be sure using DOS drive in PC and perform atiflash. ATIWinflash got me some unpredictable error, so I would avoid using it.