it's not that i7 are worse, it's that they are overkill, for 200$ you can get the best CPU for gaming (i5 3570k), for 300$ you can get an i7, but when gaming you won't really notice a lot of difference.
For knowing who is the best component in any particular moment, you need to google reviews about what you find on sale, and trust sites like TomsHardware, Anandtech, Guru3d, HardwareSecrets and others that do it as a profession (bloggers do review stuff but tend to lack the technical expertise to do it right). This page
is an example of a good review about processors, and is updated to 12 december, so it is current.
Hyper threading is a trick the CPU does to work more in some situations.
To understand this I need to make a bit of story:
Normally each core has its own list of instructions to execute (from programs, from Windows 7, from whatever). That's a "thread". Point is, due to complex technical reasons, they could be faster if they could split the instructions in two lists (threads) per core. Hyper threading does just that, tricks Windows 7 into thinking there are 8 cores when in fact there are only 4, and assign two threads per processor core.
This does a significant
difference when the CPU is doing jobs that can be split in so much threads (duh!
), like professional image/video rendering, complex calculations, in general work-oriented things.
But games aren't designed to have their instructions split in so much threads, as that would make them harder to code for their developers, rising their price (and quite a few are console ports so it's already a miracle they work at all).
The average game will take advantage of 2, or 3 threads at most.
If your CPU doesn't have or use Hyperthreading (as that can be disabled from BIOS in case you don't need it), that means it is using 2-3 cores of your processor, so around 50-70% of a good quadcore's processor power.
The same processor with Hyperhthreading has the first two threads assigned to the first core, and the third (if the game needs it and it's rare) goes to another core (together with another thread).
Which means that the same quadcore processor is now using only a core and maybe a nibble of a second core, using around 25% of its power to game, while 75% of its power is wasted.
Please note that this is an issue for most AMD processors, as they have 6 or even 8 cores (they call each core a "module" but it's the same). Since games cannot be split over more than 3 threads, you are wasting from 3 to 5 cores and it's not good, so they tend to perform worse for gaming.
why is it important to have a solid mother board, and what the differences are between 60$ and 160$ mother boards
Motherboards contain circuitry that works with hundreds of watts to run the computer components, this is a dangerous job for a gaming rig that is going to see some overclocking and you want quality components to make sure you don't meltdown everything. (also a good 80 plus
certified PSU is paramount, as cheap ones are crap)
In general, new motherboards below 100$ without a good reason are using crappy components.
As far as motherboards go, the first thing to look at is the CPU socket AND its cpu support list (everything easily reachable in the manufacturer's product page). The socket is the mount point for the CPU. As you cannot fit a square in a circle, only processors made for that socket will physically fit. The CPU support list is to make sure the motherboard is capable of using the processor. Some are cheap or designed for low-power CPUs (like motherboards for HTPCs) so even if they have the same socket, they won't be able to use your CPU.
Second thing to look for is the "chipset". It is the component responsible of operating most or all the slots and ports in the motherboard.
Newer chipsets aloow the motherboard to have more features (can control more/better ports/slots/whatever, can or cannot overclock processor and other stuff), and this drives up the price.
Third thing to look for is well, the expansion slots (what they are and what version they are). Mobos with 4 PCIe 3.0 slots (the slots for the GPU cards) cost over 300$, and frankly have debatable uses out in the real world. Mobos with 2 PCI3 3.0 slots (the most you will ever
need) are in the 100-300$ range. Also look very well at slot positioning, some motherboards have slots positioned in different ways (better or worse depending on what you want to mount and in what PC case), or may have additional slots that work only if others are not used.
Fourth thing, size. There are 3 main mobo sizes, from bigger to smaller: ATX, micro ATX, mini ITX.
-ATX is the biggest, and can mount a ton of cards but at the moment there is no real need for so much slots in the average rig. Most of these mobos fill the additional space they get for being bigger than a micro ATX with legacy PCI slots and call it a day. Unless you have already PCI cards around (or plan to buy outdated hardware), they are worthless. Yes, they space other slots better, but it's something you could fix with PCIe flexible extender cables (not for GPU slots).
-micro-ATX is the sweet spot imho. It is big enough to accommodate all expansion slots you want to have (PCIe 3.0 and 2.0), and more often than not does not blow through a 200$ ceiling.
-mini-ITX is for the most portable rigs ever
. And for other stuff designed to be small and cheap but suck at gaming like HTPCs or embedded computers like cash registers and similar. It has a single graphic card slot, the gaming ones have a PCIe 3.0. Point is, their price is around on par with micro-ATX and they offer far less expansion slots, trading that for a tiny size. Performance is on par with a mobo using a single GPU. THis
is an article where a guy makes an ass-kicking mini ITX gaming rig.
Last but not least: additional features.
Most mobos have onboard ethernet, onboard audio, onboard bluetooth and a bunch of ports you may or may not need on the back I/O panel and headers you can connect cables for front or PC case ports.
Reviews help you understand what of these additional features is better, like I said above.
In general, reviews will screen out crappy mobos, and leave only those of good brands, but in case you don't find one... Asus, Gigabyte, Asrock, MSI are good brands.
For example, my favorite board for a 1155 socket CPU (the one I'm gonna use in my new rig) is a Gigabyte G1 sniper M3. This review
is in a forum, but it's a very professional review nontheless (and Overclockers is a forum where any bs in the review would get a lot of flak).
It has the best integrated audio I've seen, it is a good overclocker and the PCIe slots are placed optimally if I install it in a normal ATX case (or a DIY one like what I want to do), while they would be annoying in a normal mATX case. And it has all ports I need. And it does not cost a fortune.