So, for thirty thousands, we can get a decent build, but not a high performance monster. here is an advise.
8,500 CPU: intel i3 6100 Skylake LGA 1151
5,500 Mobo: H110/H110M board from Gigabyte/AsRock/MSI/Asus
4,000 RAM: 2133 MHz C15 RAM 4GB X 2 = 8 GB from Corsair/GSkill
7,500 Monitor: Dell 21.5" TN Panel LED Monitor E2216H
3,500 HDD: 3.5" 7200 RPM 1 TB Internal drive from Seagate/Western Digital
2,000 mid-tower Cabinet from Antec
3,000 PSU: 430w 80+ bronze psu from corsair CX430
1,500 Acc: Speakers/Keyboard/Mouse from Logitech
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35,500 Half-life's sensible festival build
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Upgrades:
1. Graphics card
2. UPS