Hi, long time lurker, first time poster. I bought Caesar IV for the wife's pc. Installed fine, started tutorial... pc shut off. Wouldn't restart. Replaced power supply. Didn't help. Just replaced MB/CPU, thinking maybe something there fried. Didn't help. If the power supply has just been turned on, then the fan on the chipset bumps, like it got a nanosecond of juice, then nothing. If I try the power switch again, nothing happens. I have to switch the psu off/on to get even the fan bump. Upgraded from Sempron 2800/ECS mainboard to Sempron 64 3400/DFI NF3 250-AL. Upgraded from 300W stock case psu to 400W thermaltake. Have 512M Ram, 6600GT agp. BTW, when psu is on, the light on the motherboard comes on (and stays on, unlike chipset fan), so it's getting constant power. HELP!!!
as per my thoughts (memory or graphics), pulled the 6600gt out, wants to start right up..... ok, ok, not really per my thoughts. Hit the power button with the lights off in the room, got a nice electric blue light from agp area!! Good thing everything else still works!!
This may sound obsene to you, but some mb's will not boot if there's a defective ram module. Just like most mobos wont boot with a bad/ unsupported cpu. THe fans should still be turning though ...
Since you basically eliminated the cpu, mb, and psu from the equation, you dont have many options left. IF your 512 is in 2 sticks of 256, try removing one at a time. IF not, try borrowing some ram for a quck test.
Again, I've never had a mobo not boot/post on me because of bad ram, but I dont see too many other possibilities.
p.s. On the other hand, it could be the wiring. Try manually turning on your computer by quickly inserting/removing a jumper on the 2 pins where you attach the power connector from the case. It's not a switch, but rather a push-button, so dont leave it on there. DO this before anything else.