Ok, so a little background information first: I originally bought this Mac Pro V 1.1 in the second half of 2014 at a Goodwill computer store. I paid just over $300 for it and took it home. The specs are as follows: OSX 10.6.8 "Quad Core" 3.0 (two dual core Xeon 5160 CPUs) 32 GB RAM 250 GB WD Caviar 7200 rpm HD ATI X1900 GT graphics card (dual DVI) So, I bought this computer because the specs were amazing for the price and it suited my needs to video editing/rendering, torrenting, media entertainment, and internet browsing needs very well. Now for the problem: The Mac worked well for a good 6-7 months, though it ran hot, loud, and kind of smelled. Then this past May the card began to act up and I decided to replace it in July. So I hopped on Ebay and found a super cheap replacement; keep in mind I bought the same card that came out of almost the same type of Mac. So then I take my Mac and replacement GPU to a computer repair location downtown and have the cards swapped and an overnight diagnosis run. The tech said the card was a plug n' play swap and run all night no problem. So I paid the $135 bill (labor & diagnostic) and took the Pro back home. It ran fine - a little quieter and no more smell. The repair took place at the end of July and then I moved to new apartment, so use had been minimal to moderate over the last 8 weeks. Last night, the replacement card decided to crap out - all of sudden my monitor goes black and the blue no input screen comes on. Now my Pro will not even boot up. The fan to the graphics card will just whirl away until I manually shut it down again. So this morning I decided to buy ANOTHER GPU card on Ebay. This time I sprang for a refurbished ATI Radeon HD 5770 Sapphire card (1 GB VRAM, dual DVI, HDMI, DisplayPort). According to the forums here and online reviews, this was the best option for an upgrade. I also found out that the X1900 GT has a serious overheating problem and is a poor card to work with. After buying the refurbed card, I called a couple local computer repair places to get a quote on installation. The first place (Mobile) said installing the new card would run $89 and $45 for a diagnosis. The guy on the phone said that he knew a guy with a similar problem - his friend had an iMac and was eating card after card. He suggested that my board was feeding the card too much power and burning it out. So basically he said my motherboard might be faulty now, but he has "experience" to deal with the problem; either replace capacitors or the whole board. I have been to this location before, back when my external HD broke, so I kind of trust this place. The second place I called (A & G) said the installation would only run $40 and he would also inspect the board while he was in there. I mentioned the possible board issue but he said it sounded more like a card problem. I decided to run down the store and show him the first card that came out. He took one look at it and said nothing on it looked blown-out or damaged. He explained that graphic cards are designed to deal with power variances from the board and unless the amount is under like 10 volts, it should be fine. He also said that if any of the capacitors on the board were blown, they would looks "stringy" and that a board is either good or bad. We got into a discussion about the replacement (which he swears by and said a stock 5770 would work instead of the "Apple" flashed version) and repair options. He said that installation was no biggy and suggested I switch the card to a different PCI slot. Then I came back home and mentioned the problem to a friend on Skype and he automatically responded that the board was overfeeding the card. So I'm at a total loss here. My next replacement card will be here in a couple days and I don't know if: a) I need to just swap the cards myself and hope like h3ll. b) I need to have the board repaired/replaced. c) Get the Pro running and dump it on Craigslist for any $$$ I can get for it. HALP MEH, PLZ!!