Been doing some reading and I've got some conflicting information, reaching out for more insight. I would like to run a 5870 and 5770 in my mid 2010 mac pro. The core issue is that the system has 2 PCI-e 6 pin power adapters, the 5870 needs 2 and the 5770 needs 1. The 2 resolutions I've found are: 1) Add a second PSU 2) Split one of the 6 pin connectors with a Y adapter The PSU will work, plenty of power, however it's another PSU, that's space, expense, weight, power draw, complexity, etc. The splitter should work (according to people claiming to have used it), and the system's PSU should have more than enough power to run both cards even under load. I'm inclined to think that the Y adapter will work fine (I've seen plenty of PC configs that include splitters for their graphics cards). But it's still kinda sketchy since the 5870 has 2 plugs, there are 2 plugs... you're draining some of that capacity from one plug for the 5770... Thoughts, insights, etc. Not looking for "PSU is safer" or anything vague like that, but if there's a real problem with the Y adapter approach what is it specifically. Are there not enough amps under full load of both cards due to a limit on the draw of each connector or what? Would an issue only be likely to show up under a certain config (full 6 monitors, only if all 6 were running full dual link resolutions?) or under certain situations (maxing out the 5870 and then begin maxing out the 5770, the 5870 gets starved and crashes?). Any reasoned insights would be greatly appreciated!