what cooler do you have?
if you have the stock one my suggestion is to pretty much forget the 4Ghz 200BLCK ... If it is you first time oc'ing I suggest reading and re reading all the oc (especially i5 overclocking guides) you can before you touch anything
overclocking can break stuff ....especially if you enter the wrong values but the danger of stuff breaking even if you do it "right" exists now this going in.
what are you idle and load temps like now?
so I have a i5-750 with a gigabyte h55m-u2dh mother board with a hyper212+ cooler I run 166x20 with turbo boost enabled and the various c-states on i don't feel the need to push it harder than that nor do i wish to have to bump the voltages up and increase power use to go to 200blck
i think this guide is pretty good I read it when i got my i5 maybe it will help you also.http://www.bit-tech.net/hardware/cpus/2 ... e-i5-750/1
if it was me i'd make sure i have my ducks in a row cooling wise and studying up on overclocking before I touched anything in the bios
edit...oh right reading for comprehension is FUN...so you built their budget gaming rig with probably wasn't using the stock cooler ..