Ok, first time trying to build a computer, so I apologize in advance for any dumb questions I have to ask. I've been through the "Read this" post, and fixed a couple of things I'd messed up already (plugging all the power plugs in, resetting the cmos....), but still having problems.
I can't get the BIOS to POST in a way I am sure of (no beeps at all ever). I have pulled the mobo and cpu completely out of the case (stripped the vc, drives and memory), reattached the psu and get nothing (except the fan on the HS spins). Now, I had the system bring up the BIOS interface at one point, but it errored with a "IDE / primary drive not recognized" and power-cycled on confirmation of the error. I shut the system down to confirm I'd hooked up the drives correctly, but then could no longer get a video signal.
So here's my question: is this likely a mobo failure? or the cpu? Have I missed something REALLY simple? The drives, fans, vc, etc lights all came on, so I think my PSU is ok. I'm trying to follow the "breadboarding" process, but am stumped at step 1. I don't have any additional equipment to test with (trying to replace an antique...)
CPU: AMD Athlon II X4 620 Propus
Mobo: GIGABYTE GA-MA790GPT-UD3H AM3 (AMD)
PSU: Corsair 650W
Case: Antec 900
Video: SAPPHIRE 100245HDMI Radeon HD 4850 512MB
HDD: Western Digital HDD
RAM: Crucial 2GB 240-Pin DDR3 SDRAM DDR3 1333 (3x)
Did you perform steps 6 - 8 in the checklist to rule out RAM as the problem? You should try each stick by itself in the first RAM slot. What exact RAM kit do you have? "DDR3" doesn't really tell us anything.