As long as you take proper ESD precautions and research your parts compatability properly it's safer than it's ever been.
Motherboard choice will be dependent on CPU choice.
RAM is easy - DDR3 is pretty much the only standard in use ATM (mid 2012), DDR2 is considered legacy and DDR4 isn't ready yet - higher numbers are compatible with lower requirements. High end systems (Sandy Bridge-E at this point in time) use a Quad Channel RAM configuration which means you need multiples of 4 sticks of Matched RAM. Mid to High end (most of what an enthusiast would WANT to build) uses DUAL Channel, i.e. multiples of 2 sticks of matched RAM. And low end setups still use single channel, so you you can mix and match brands and capacities across the board.
Pretty much all Graphics cards are PCI express now however just make sure you have adequate PSU power. Here spending more really does make a difference. A name brand 400W such as Corsair is miles better than a no-name brand "800W" (hint the 800W isn't).
Beyond that just be patient, research component compatibility (if in doubt ask) and you should be fine.
6clarification: ESD = static electricity. even if you don't feel a 'spark' you can generate huge amounts of it that will kill CPU's. you can buy special static discharge wristbands so you don't fry components – geocoin – 2009-07-16T14:31:47.493
1The compatibility research was the bit that made my head spin last time I considered building my own machine - at that point, I said "stuff it" and asked the shop to do it for me to my specifications. – Margaret – 2009-07-16T14:45:49.283
yeah it does take a bit of forcing your way through it... especially as there is huge 'Alphabet soup' among the specs. best thing to do is usually have an idea of what you want e.g. CPU, MOBO features and graphics, then run the selection by a tech forum (such as SU???). So for instance i might know that i want an intel quad core - I already know i7 is too expensive, so know that i want a P45 chipset (based on research, so then just need suggestions for RAM and HDD. http://www.bit-tech.net is doing monthly What to buy features which are really good
– geocoin – 2009-07-16T14:56:38.563ESD preventive measures are overkill in countries/regions where humidity tends to be really high (over 80%). For basic protection, try not to work over a carpet, and touch doorknobs from time to time, that should do. – Manuel Ferreria – 2009-07-16T15:47:04.207
1if humidity is over 80% I'd be more worried about dripping sweat onto the components ;) – geocoin – 2009-07-16T15:59:09.440
I wrote a simple how-to not too long ago that might help out figuring what parts are compatible and what you need to look out for: http://files.getdropbox.com/u/1546882/building_computer.pdf
– Travis – 2009-07-17T00:48:07.287Touching most regular doornobs won't earth any static from you, it's much easier to touch the case of an earthed PC. – HaydnWVN – 2012-07-31T13:30:11.250