400R case - does it need standoffs? Not getting video on new build

I've built two computers before, so this is my third. I put it all together, plugged it in, fans turned on, but no video to the monitor. I tried using an HDMI cable and then a DVI cable (both confirmed working on another machine), but still no video after a few minutes. It also wouldn't turn off when hitting the power button either time (one with each type of cable), I had to do a hard power off.



I figure the problem is related to one of two firsts I've had with this build:



1. Modular power supply

2. Case appears to have standoffs built-in



I guess you could also say this case has built-in fans, which I haven't been able to get working, but that's a problem I'd rather resolve after this main one.



4 copper standoffs came with the 400R. I did a lot of research online, and everything I found says "the standoffs are built-in."



So I trusted this, and built it.



Now I'm nervous those standoffs needed to be used somehow, even though the motherboard is totally level and I imagine putting the standoffs in anywhere would make it not level. Can you please confirm this case has built-in standoffs? If so, I plan to then try and do a check if the RAM is bad. Please let me know anything else I might have missed. An extremely poor picture can be found here: http://ift.tt/T5agYx. Here's what's plugged into the PSU:



-Main mobo connector

-CPU connector

-2 SATA connectors (one for a DVD drive, one for 2 HDDs)

-1 PCI connector (for video card)



That stray cable near the bottom of the PSU is something I thought was related to the built-in fans, but have left alone for now. This is also my first real attempt at cable management. I have a lot to learn.



Thanks!