One of the things that I've heard a lot about is chains. I started with a regular cross cut chain, this worked just OK, it was a lot of work to cut the hard wood, and left a very rough surface.
Next I re-filed my chain to what is called a ripping chain by some, this is where the cutters are filed to a 5 degree angle on the cutters, but no cutters are removed. This was an improvement over the standard cross cut chain, and I think it would work well on softer wood, but on the hard wood I was cutting it was not so great.
I next got directed to the Granberg style of ripping chain, the Granberg style Ripping chain has a set of teeth that have had every other set (pair) of top plates removed. (A set meaning a tooth from each side when possible. See the picture below.) You would take 2 teeth next to each other, one on one side and one on the other, and grind off the top plates using a bench grinder, Dremel, or belt sander. You don't shorten the tooth at all but merely remove the top plate that sticks out to the side of the side plate. What's left on top is nothing wider than the thickness of the side plate.
The tooth with the top plate removed now goes through the wood with less resistance than pulling a top plate along with it and effectively severs the wood fibers. The next set of teeth to go through with the top plates, clean out all the severed fibers. This results in less heat buildup, faster chain speed, and smoother cuts with reduced clogging.
This set up was a great improvement, the saw worked so much better using this chain.
I could keep the saw hogging through logs all day long, the saw would run just below the "four stroking" you get when a saw hits it's rev limit, which is the peak of the saw's power band, right where you want your saw to be running.