Need help

[HBB53]

So I just helped my friend build a pc with a r7 2700x, Vega 56, Corsair lpx 16gb 3200. 
I’m an experienced pc builder and I’ve never seen anything like what’s happening. We try to boot and it goes straight to a screen on the monitor and says no signal. All cables are plugged correctly. Trying to trouble shoot, any help appreciated 

[minibois]

So you have your monitor plugged into the GPU (not the motherboard), turn it on and the monitor goes no signal? What does the PC do? Any lights, post codes/LEDs? Any fan movement?

Also, while I personally have never experienced this, people often say 'AMD takes a longer time to POST the first time', so have you let it sit for a minute too?

[Votivee]

I'd try (In this order)

• Boot with one stick of ram (or different ram if you have it)
• Different GPU
• Different PSU

Do you have any post codes?

[HBB53]

Yes, the asus rog strix b450 shows shines a white light. All of the fans are spinning and the rgb is running, the pc is giving power to the mouse and keyboard  so I’m not sure 

[YoFavRussian]

26 minutes ago, Minibois said:

So you have your monitor plugged into the GPU (not the motherboard), turn it on and the monitor goes no signal? What does the PC do? Any lights, post codes/LEDs? Any fan movement?

Also, while I personally have never experienced this, people often say 'AMD takes a longer time to POST the first time', so have you let it sit for a minute too?

Had to restart mine about 3 times for it to actually correctly POST, didn't do anything between each Post, it juts eventually posted.

[HBB53]

Ok, we got it up and installing windows now but we have a new problem. I went and got my gpu to test his mobo and it’s working so we went on with downloading widows but the display just went from a windows blue to a weird purple color and idea why?

[xFetusx]

That seems to be somethngi with the AMD drivers (older drivers but not super old)  and was supposed to have been sorted , i think linus touched on that recently (or another tech tuber i forget off hand) but thats what happens and you need to reboot to fix it .

[HBB53]

Okay thanks man