I have been slowly upgrading my system lately and have discovered that it's not always easy to know what your exact bottleneck is or can be. I have decided to share my experience, to help others realize that sometimes when you think one thing is your bottleneck, it can very well be something else.
Let's start off with what my 'original' system was before the 'upgrade rush' of 2014. I had an Intel i7 2600k which was overclocked at 4GHz, running on a Gigabyte Z68X-UD4-B3 with G.Skill Sniper 2x4 GB 12800 (1600 MHz) DDR3 RAM, Intel 320 160GB (which is SATA 2) and a MSI GTX 560 Ti (with only one fan working).
I was fortunate enough to have access to this past winter's Intel Retail Edge deal, allowing me to pick up an Intel i7 4930K Desktop Processor and Intel 530 Series 180GB (SATA 3) SSD for a great deal. Thanks to Soullessone21, I bought one of his motherboards (MSI X79MA-GD45), added to my plan of keeping the cost of the upgrade quite low. Selling off the LGA 1155 motherboard and processor also helped with off-setting the upgrade cost. Setting up the entire system I found I was not able to overclock the 4930k that well with the current RAM that I had, able to get to about 3.8GHz.
I began to play games, not really noticing that much of a difference in load time, probably as minor with the upgrade of the SATA3 SSD from the SATA2 one, though nothing that screamed out that I've made a large performance jump.
Now we get to where I start to 'benchmark' how long it takes to load a level in Mass Effect 2 (namely as I had recently started going through the Mass Effect trilogy). With the most recent setup, I was noting load times between maps or levels to take about 10-15 seconds if it was a large one, and about 5-7 seconds when it was a smaller one. For any gamer, any sort of load time can seem extremely long, so I decided to upgrade my RAM, replacing what I had with g.SKILL Trident F3-2400 (2400MHz) 4x4 GB Quad Channel Memory. This allowed me to not only overclock my 4930k to 4.0 GHz (I am just running on air), it also cut down the loading time to about 6-9 seconds on large levels and 3-4 seconds on small levels.
As I plan to do some video game reviews soon, Soullessone21 sent me over a MSI GTX 770 to replace my slightly aged GTX 560 Ti. Now this is where I noticed the largest load time improvements. By that I never see the loading screen, large levels or small levels load within a second.
Sure upgrading from a Sandy Bridge to an Ivy Bridge-E may not much of an upgrade in processing power for games, same goes with upgrading from 1600 MHz RAM to 2400MHz RAM, the more important upgrades I noticed were going from a SATA 2 to a SATA 3 SSD and a GTX 560 Ti that may only be working at 3/4 to 7/8 of it's normal performance to a fast and silent GTX 770. So remember, just because you think something is your bottleneck or is slowing down your system, it may not always be the case.