stuck at boot (gray Apple logo with spinning gear)

[BatterseaPS]

Hi, this problem has me really worried because I haven't had major problems with my Hackintosh yet.

 

I've been running Lion smoothly for a month now, but a few days ago the computer stopped booting. It now gets stuck indefinitely on the boot screen, after it recognizes and selects the HDD as the boot device (the HDD then makes some noises as if it's accessing something, but it never boots).

 

Through some quick searches, I see that I should try accessing safe mode, but I don't know how. I tried typing -x at the boot screen (is that right?) but it didn't do anything.

 

I'm using Chimera, although I don't really know what that means (are Chimera, Chameleon, and [url="http://www.insanelymac.com/forum/topic/279450-why-insanelymac-does-not-support-tonymacx86/"]#####[/url] mutually exclusive things? I'm not really familiar with their functions).

 

These are my components:

 

GIGABYTE GA-EP45-UD3P Intel P45 ATX Intel Motherboard Intel Core 2 Quad 3.0GHz LGA 775 95W Quad-Core Processor GeForce 9800 GTX+ 512MB 256-bit GDDR3 PCI Express 2.0 x16 Patriot Extreme Performance 8GB (4 x 2GB) DDR2 800 (PC2 6400)

 

It's also possible that someone else using the computer updated to 10.7.1 without me knowing, but I doubt it, since I turned off the auto check for updates.

 

Thank you so much for any help, since I'm starting to panic a little.