Elena

Found the problem. For anyone else experiencing the same issue or similar connectivity issues: I use a 2.4 GHz connection for my keyboard which coincidentally, every time i turn it on on startup, it glitches out the internet connection (which is also on 2.4 GHz). The connection stabilizes after some time, but I guess I'll be using the keyboard through Bluetooth for the foreseeable future.
Thanks again for your help @TimedPing

Definitely PSU. Since you didn't list it, I will assume it's a dodgy low powered one that came with the case. By plugging in your phone, the power supply goes over the surge limit and does an emergency shut down.

It's a probably a PSU problem. Could you post the exact model of your PSU(power supply)? Alternatively, try a different USB cable.

Some 750Tis do not need external power. I would get that card. You would not need a New PSU. 

Have you OCed the A10 to 7.6 GHz.?!?!
 
Anyway, the 750Ti will work fine, and there doesn't seem to be any sort of compatibility issues with any parts. I believe the A10 will not bottle-neck the 750 Ti, but if you're gonna go higher (like GTX 1060, RX 480) in the future, you better change the CPU. The power-supply will work OK for now, but isn't recommended for extended usage at all! Please do get a very reliable PSU, at least the Seasonic M12II 520 (80+ Bronze 520W Semi-Modular).

Good choice! Generally Seasonic PSUs (at least M12II-series and above) are very reliable, and 80+ Bronze is not condemn-ably inferior to higher 80+ ratings. So go for it! You can visit the product page of the PSU, where they'd definitely put up such specs. But before buying any component, read up on numerous reviews on reputable websites, even if you the product is the best of best - it might probably lack a certain feature you'll require, or there may be small issues. So, if you plan on investing in a Seasonic M12II 520 EVO, read all the reviews on the internet, and make a wise choice. Good luck!

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