Powers On but No Video
I recently came across what seemed like a good deal on a handful of 2008-era Mac Pro desktop machines. Of the three I picked up, one turned out to be a dual-processor G5 machine, and the other two are dual-processor Xeon machines. The Xeon machines are the ones I'm trying to resurrect.
None of the machines had hard drives or video cards. I bought a couple of new hard drives and a couple of new (MSI F5450 MDIGH) video cards, installed one of each into each of the two Xeon machines, and pressed the button.
Both machines turn on and the power lights are on steady. But I get no video from either machine (I have two monitors plugged into each - one via HDMI and one via VGA). I don't understand why I'm not getting any video (and no video is making it hard to troubleshoot anything else). Is it because there's no drivers on the brand-new hard drive?
For what it's worth, I opened up the case and started each machine, and I see no LED indicator lights anywhere inside (I think there are supposed to be some, but I don't know where).
Today, I connected my MBP to one of the machines via Firewire and started the Pro in Target Disk Mode. I immediately got the "The disk you inserted is not readable..." dialog on the MBP and used Disk Utility to format it. Then ran OS X installer and installed Yosemite on the newly-formatted HD in the MP. Unplugged everything and restarted...still nothing.
Any ideas on what's going on here?