Let’s assume you are willing to buy your parts and build your PC.
I found you this decent entry level build coming in at $532 at the current market USD. This list WILL change based on preset factors that match the criteria you need. Prices and parts may very, make sure to check the link.
System Builder - Pentium G4600 3.6GHz Dual-Core, GeForce GTX 1050 Ti 4GB, XON-310_BK MicroATX Mid Tower - PCPartPicker
CPU: Pentium G4600 $87 - The G4600 is currently on sale for less than the G4560. The G4600 is undeniably a better CPU, but only by a small margin, but when it’s cheaper, it’s a steal.
Motherboard: AsRock B250M-HDV $55 - Good, small, cheap. Great for a low-end CPU with locked overclocking.
RAM: Crucial Balistix Sport 8GB (2x4GB) $70 - Cheapest 8GB kit on the market currently. It should serve you just fine.
SSD: SK hynix SL308 250GB $79 - My honest opinion is that an SSD is mandatory in any PC build nowadays. It will greatly improve your load times. If you need the extra space and can forgo the SSD, check out the WD Blue 1TB for $41 or the Seagate Barricuda 3TB for $75
Video Card: GTX 1050 Ti $157 - Amazing card, I have one myself. Guarantee it will run every game at 1080p at 60fps at Med-High settings.
Case: Thermaltake Versa H15 MicroATX $38 - Cheap, small form factor and highly rated. Case is always personal preference, so maybe look around a bit. If you have an old case lying around, re-use it and save the money. Cases aren’t that important in low-end machines that don’t produce a lot of heat.
PSU: Corsair CXM 450W 80+ Bronze Semi-Modular $47 - 450W 80+ Bronze is all you will really need for this system. Given your case is so small, I threw in a semi-modular supply as well, it should help with cable management but it’s not required. Feel free to swap this with anything above 430W 80+ from a reputable brand. (EVGA, Corsair, etc)
For More info:http://www.gaminginstincts.com/