Actually I went from an OC'ed 965 to an OC'ed FX-8350 and the performance increase for my use (no games) was substantial.
As far as cooling is concerned there are plenty of good HSFs that out perform AIO/CLCs and many HSFs cost half the price. As an example there are over 100 better HSFs than a Corsair H60. Objective scientific cooling tests document that AIO/CLCs are thermally inefficient, noisy and expensive compared to a quality HSF that never leaks water to short circuit and damage your expensive PC hardware.
The bottom line is H2O cooling has a very real water-leak liability that can cause lost data, burn up your PC or worse and leave you up the creek for weeks. If you're OK with that then about the only H2O cooling worth buying would be an open loop custom system and they start at about $200 and go up. Then you'll be doing algae and system maintenance to try and keep the system from plugging up. Why someone would want the liability and hassles of a H2O cooling system is beyond me. I suggest people get the FACTS before they get duped on H2O cooling.
As far as RAM frequency, for a descrete desktop CPU RAM running at ~1600 MHz. or higher is not a system bottleneck thus there are only minute system performance gains from higher DDR3 frequency. There is a lot of test data with real apps online to substantiate this. RAM benchmarks show theoretical gains not actual gains which are very small if at all.
On APUs where the GPU section needs bandwidth, DDR3 up to ~2133 MHz. shows modest system gains. Beyond that there isn't anything tangible at this point in time.
Building a reliable PC involves more than just assembling the parts. You need to be able to configure all of the BIOS settings appropriately. This can be quite involved and frustrating as it can require a lot of trial and error with stress testing. It is however often the only means to get a 100% reliable PC.