Torchlight 2 will run fine on about anything. Civ IV...it depends on how smooth you want it, for long games. It doesn't really hinder mdoern CPUs, but can get a bit sluggish with slow cores. Avoid Bay Trail, Kabini, etc..
PCPartPicker part list /
Price breakdown by merchant
CPU: Intel Core i3-4130 3.4GHz Dual-Core Processor ($108.97 @ OutletPC)
Motherboard: ASRock H97M Anniversary Micro ATX LGA1150 Motherboard ($66.99 @ SuperBiiz)
Memory: Team Dark Series 8GB (2 x 4GB) DDR3-1600 Memory ($57.99 @ Newegg)
Case: Silverstone PS08B (Black) MicroATX Mid Tower Case ($33.99 @ SuperBiiz)
Power Supply: Corsair Builder 500W 80+ Bronze Certified ATX Power Supply ($29.99 @ Newegg)
Optical Drive: Asus DRW-24B1ST/BLK/B/AS DVD/CD Writer ($18.75 @ OutletPC)
Total: $316.68
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-12-20 18:53 EST-0500
No OS, no HDD, 1 MIR. A video card would be a nice add-on, but the IGP should handle both games alright. Windows 8, cheap, basically requires getting a prebuilt.
So, with that in mind...
http://outlet.lenovo.com/outlet_us/itemdetails/90B80010US/445
Not amazing, and will only take low profile cards, but includes 8.1, the IGP is faster, and it can take video cards, at least.