Make warranty call, 1st. But if they offer that you open case and check innards to see if anything has fallen down or is eschew, etc.. If nothing seems wrong and you've reseated the cards and cables, etc. and still no go, you've done pretty much all you should do. You're next action is to try any warranty service. Do so NOW!!! you're on the clock and they're suppose to fix it. I strongly suggest you return it because they will drag it out until that warranty period is exhausted. -OR- flat out get your CC to cancel the billing and return once you have a RMA#, follow procedure. Don't argue just be strong and reasonable. However, if it's this way on day 1, I fear it can be worse much later. Put it all down on paper and get names and times, etc., record your actions with them.
tada ------Willy 
I ordered a refurbished HP Compaq dc5850 Desktop PC - AMD Athlon 64 X2 2.3GHz, 4GB DDR2, 750GB HDD, DVD-ROM, Windows 7 Home Premium 32-bit, Mouse & Keyboard (Off-Lease) from TigerDirect.
After attaching a cheap used VGA monitor and the supplied USB keyboard and mouse, I powered it up. Lo and behold, nothing showed up on the screen. The screen was powered on, but it showed as having no juice.
The DVD roared alive. And was able to open and close.
The mouse and keyboard were not lighting up.
When I placed in the Windows 7 Rescue disc, and reset, same story. Nothing.
So I tried hooking up a DVI monitor, that I knew for sure was working. Again, nothing.
So what do you suppose is pooched?
If it's not worth trying to resurect this PC, I'm in the market for a used, reliable low-end PC with similar specs. I'll be grateful if someone can point me in the right direction.
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