Yes, you can indeed overclock it. Provided you have a decent cooler (it isn't listed so I don't know), that CPU will probably reach 3.2GHz with little trouble.
What are you using it for? I'd imagine the 9800GT will be the bottleneck if you are using this build for gaming.
10tacle :
I'd be hesitant on overclocking a chip nearly nine years old. It's only a matter of time before either the CPU or motherboard fails - why help it along to the inevitable by overstressing it? I'm also surprised you were able to get Win10 to work on such an old build.
CPUs last a heck of a long time. I still have a Socket 939 (the date stamp on it is from mid 2006, so its now 11 years old) Athlon 64 X2 that is still running perfectly happily overclocked, as well as a 45nm C2Q-era Xeon that is running at 4.1GHz with no signs of quitting any time soon. Both of these are older than the i5-750 in question, so I'd say you're probably fine. Yes, overclocking (well,
mostly overvolting, but that usually goes hand in hand with OCing) does reduce the lifespan of the chip a little, but the lifespan is likely measured in decades, so that doesn't matter too much - it'll probably become too slow to run modern programs well before it actually physically dies. Just look at the Pentium 4 and older Athlon 64/1st gen Phenoms.
As for Windowes 10, Lynnfield is by no means a slow chip. Sure Sandy Bridge and beyond is faster, but they are still pretty powerful CPUs. Also Windows 10 runs great on some pretty low end systems - the only thing I haven't had Windows run completely happily on was an old Atom 330 HTPC (which still ran W10 pretty well, it just stuttered a little now and then due to the weak processor and the fact that the board was maxxed out at 2GB single channel DDR2 533MHz).
Kenton82 :
I am trying to find out the best way of overclocking my i7 950 at the mo. and as its 9 years old now, as a pc its almost worthless (apart from the PSU and GPU)
An i7 950 is by no means worthless. Sure they can be had fairly cheaply these days but they still perform pretty well. I mean I have a Core 2 Quad based Xeon (E5450) that runs most games fine, and a lot of the time when games perform poorly, I'm being limited by my GPU - a GTX570 - rather than the CPU. A Nehalem chip is much more powerful than my Harpertown, so I would think you could still run most games pretty well when using a decent GPU like a GTX 1060 or RX 480.
Jake_142 :
No, it is locked. but if you know how to unlock it then 3.3 ghz is good enough
The 1st gen core i series could be overclocked without an unlocked multiplier. The system bus clock (BCLK) on 1156/1366 systems ran at 133MHZ, and was not tied to everything like SB and newer. This meant you could raise it much higher than on modern core i systems, and essentially overclock like most previous FSB based systems.