Since you have not stated a purpose for this cpu , just that you want to over clock it to a certian speed . The stock speed on this cpu is 3.6 ghz and you wouldn't be doing much overclocking. You can however overclock this cpu up near 5.0 ghz.
For $200 you won't be able to get an Intel cpu that you can overclock as they need to be an unlocked multiplier. This is as close as you can get to an unlocked multiplier and $200 budget. There are others that you can get but they can only be overclocked slightly by raising the front side buss.
A cpu like this one has a turbo boost of 3.7 ghz and will be engaged when the system needs the cpu to use the boost. o that it would negate the need to overclock to the 3.8 ghz unless you wanted to go higher.
In my opinion your best choice is a AMD FX 8120.It will overclock lower than a FX 8150 but doesnt really matter since you'll only be pushing it to 3.8GHZ.You can overclock to that frequency even on the stock cooler!
I guess with that one you wouldn't have to overclock it since the stock speed is 4.2 ghz.
You still haven't told us what your using this for and it does make a difference. Not everything is all about what the stock speed and what it can be overclocked to.
I can understand why you are interested in the AMD FX-4170 Zambezi 4.2GHz , it's because of the price $119.99 andI don't blame you that's a pretty low price but it may not do what you need it to do and then again it may but not at a very good speed even when overclocked.
Yes you can still overclock the 4170 even higher than the 4.2 ghz.
My recomendation is for the Intel cpu but you can do what you choose to do since it's your money and your choice. You came here asking for advice but in the end you can choose to go with your choice regardless of what is recomended.