Can't start computer with new motherboard

[mattgrayson]

Hi everyone,
New poster here 
I have a Gigabyte GA-F2A88X-D3H which came fitted on my desktop that I acquired from Cyberpower (I know).
The computer always had a problem with flickering lines of static across the screen followed by the graphics crashing.
I replaced the graphics card, replaced the RAM but persisted and eventually fell out of warranty.
I decided to try if it was the Motherboard so searched the same one. I'm not a computer expert by any means so thought it would be easier to do a like for like switch of cables to ensure they're done right.
I actually got the GA-F2A88XM-D3H. I'm unsure what the M stands for. The board is smaller, there's no Ultra Durable thing on it but seems the same other than that.
I've carefully replaced all the cables like for like.
When I went to power up, there was nothing. I turned round the POWER SW plug and now while I hold the POWER button down, the fans turn on the CPU, System Fan and Power Unit. The LED lights come on but flicker. When I let go of the POWER button it all closes down again. Nothing boots up and no power other than the fans and LEDs runs through that I can see or hear.
I've added 2x 4Gb Hyper X RAM sticks and a Radeon R7 dual graphics card.
Any help would be appreciated and I thank you in advance 
Matt

[dmdilks]

Looking at both boards make sure you don't have stand off in the wrong. The mounting holes are different.

[mattgrayson]

Looking at both boards make sure you don't have stand off in the wrong.

Hi, thanks for the reply. Youll have to excuse my incompetence with computers. What does stand off in the wrong mean?

The mounting holes are different.

You mean to mount the Motherboard to the case? Yes they were millimetres put though. Is this a problem? Would it result in a complete loss of power?

I've replaced the old motherboard to still use my computer while trying to solve the issue and Power goes through but nothing to the keyboard or monitors. 
I can't win! 

[dmdilks]

If the standoff is touching the board it could shorting it out.

[mattgrayson]

Thanks for all your help so far 
I've taken it apart and rebuilt it being really careful to ensure that the Motherboard is aligned with the screw holes. I don't think I can get it any closer. The board is smaller than the last one, the bottom section has no off loaders that are in line with the bottom holes. So it kind of just hangs there. I don't know if that could be part of the problem, but I'm unsure how to remedy it.
The only part of the rebuild is the ports that the SATA Plugs go into. I've attached a photo of the current situation.
The Hard Drive is going into number 4 and the other thing ( I have no idea what it is - a cream box that says SATA data and SATA power on the back) is plugged into 0.
Could they be wrong? They're the only part I'm not 100% about plugging back in. 

Edit: I took and attached a pic but can't see it. I'm working off my phone so struggling somewhat. Let me know if the pic isn't there

[dmdilks]

I'm just asking do you have the front plugs plug in right. Could you have the reset plug in the power connector and power plug in the reset connector.