If you are shopping around for a cheap monitor you have more or less restricted yourself to TN panels. Not sure where you are exactly so prices will obviously vary.
As Millz pointed out, if you are doing anything except gaming you will want to look at IPS or PLS panels.
The nice thing about TN panels is that they are fast and they are cheap.
I don't think you will be able to find any panels at 120 or 144hz for your price range so I would look for something with a low response time.
Say 1ms? prefect.
My personal choice would be this:
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This monitor was made for gaming and should do you well. The response time is 75% faster than the 4ms one. Although both are stupid fast. It has 2 hdmi ports which to me is handy. The downside of this monitor is that with the colors aren't true. most people rip on TN panels saying they're shit but most of us having been using them for years already and wont mind.
If you were willing to give around 50 more for your monitor you can pick up a nice 120/144hz monitor.
The
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Runner up here is the
You must login or register to view this content. which depending on which one you get (revised or old version) will come with 120hz/2ms delay or 144hz 1ms delay screen.
Goodluck. hopefully you will look around a little bit more. I don't know that market as well so there might be better or cheaper monitors. Also good to keep a look out for sales! =D