Graphics card shows nothing

So i bought a r9 280x toxic for my system and have a 8 pin and 6 pin connected to it from the PSU which will power the fans and lights upon it but when i plug it into the monitor i get no signal, I've also added another PSU so it has 2 8pin connections but still nothing. The motherboard also has been updated to the most recent bios. At the moment i'm using my inbuilt graphics and they work relatively OK for basic tasks but the GPU doesn't even shows up in device manager. What should i do?

 

Hi themarco212 and welcome. Please post you system specs from this link and also include the name, model, and wattage of your Power Supply Unit. http://static.techguy.org/download/SysInfo.exe

 

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 8.1 Pro, 64 bit
Processor: AMD FX(tm)-4130 Quad-Core Processor, AMD64 Family 21 Model 1 Stepping 2
Processor Count: 4
RAM: 8174 Mb
Graphics Card: AMD Radeon HD 7700 Series, 1024 Mb
Hard Drives: C: Total - 1430445 MB, Free - 684566 MB;
Motherboard: ASUSTeK Computer INC., M5A78L-M/USB3
Antivirus: Windows Defender, Disabled
PSU: Alpine 750w PSU http://www.amazon.co.uk/Alpine-Quiet-Silent-Power-Supply/dp/7135799380

 

I'd try cleaning the connections and blowing out the slot it's installed in. If that doesn't work, since you've had the same issue with 2 PSU's the card you bought may be bad.

 

Alright thanks