If you don't want to spend more than say $80-110 or so, then a Radeon 7750 or a discounted 7770 is your best choice. If you don't mind spending more, say up to $160-190, a Radeon 7850 is your best option and is especially good for cheap 1080p gaming. A little more at around $210-240 would mean that the GTX 660 and the Radeon 7870 are viable options. These are USA prices, so if you're not in the USA nor Canada, pricing might be different.
The 8120 has a lower clock frequency and lower power consumption. That causes a considerable performance difference because they are otherwise identical in hardware. You can buy the 8120 and it will overclock equally well to the 8150, but if you don't want to overclock and want more performance, you'd have to pay for it to have the higher frequency. It does matter for what you want to do, but IDK if it'd matter so much that the 8120, even without overclocking, wouldn't be adequate for your uses. It's very roughly 15% slower than the 8150 if you don't overclock it.
For gaming, most LGA 1155 i5s are better than any AMD CPU without overclocking and/or other tricks that you can do with AMD CPUs that you can't do on Intel CPUs. For virtualizing, K edition i5s (those that support heavy overclocking) aren't practical because they lack certain features. Even the non-K edition i5s are weaker in highly-threaded performance compared to the FX-81xx CPUs, something that can be very important for virtual machines. It'd kinda be a trade-off like this: more gaming CPU performance for less virtual machine performance.
An LGA 1155 i7 would have comparable highly threaded performance to an FX-81xx CPU (sometimes a little higher, sometimes a little lower, depending on the comparison) as well as nearly identical single/lightly threaded performance to an i5.
According to US prices, you'd have to pay more for an LGA1155 i5 than for an FX-81xx CPU and much more for an LGA 1155 i7 than for even an LGA 1155 i5, but IDK how prices are in India for this.