Pc Problem Please Help

I was wondering if anyone could help give me an idea what is wrong with my pc :? when I turn on my computer it crashes at the emachines logo at the very start of turning it on. Sometimes it will load pass this if I'm lucky :P then I use it for about 5 mins and all of a sudden it will crash. Anything connected to the usb ports won't work and the fan seems to make a louder noise, if anyone could give me some suggestions for the cause of the problem is I would be very grateful. Thanks ;) Pc Problem Please Help
Did you touch anything inside the case e.g change a graphics card etc? Did you overclock a cpu or gpu??Pc Problem Please Help
Generally speaking you have either a hardware issue or a bad configuration in your BIOS. You will need to do further troubleshooting to know for sure. Most BIOS's have a ''fail safe'' option. Try loading that up and see if the problem goes away. If not, there is a good chance it is hardware.Before trying to troubleshoot the hardware, you may want to try completely clearing the CMOS. There will either be a CMOS jumper or button on your motherboard to accomplish this. Press the button or boot your PC with the jumper removed to clear it. If it appears to be hardware related, you will either need to send your PC to someone with the proper diagnostic equipment, or troubleshoot it with a trial and error approach, i.e., replace stuff until it fixes it.Have you made any hardware or BIOS changes recently?
If you can't find the CMOS jumper, you can remove the CR2032 BIOS battery (basically a big 3v battery somewhere on the motherboard) leave it out for about a minute or so then insert back into place.Most BIOS models will have a section called Hardware Monitor, you might want to go there and watch out for high temperatures on the CPU / motherboard (high as in 65-70 or even above!!).If resetting the BIOS didn't work, then there might also be a slight chance it's a PSU-issue. Did you connect any additional device to the PC like an expansion card / a new GPU etc (even a USB device) ? If so, try to disconnect that specific device and try again.Also, tell us how your testing goes along... Tell us which one of these 'solutions' worked or failed.
Thanks for the advice :) but before I had a chance to read your posts my computer was fixed somehow :question: what happened was it somehow got past the emachines message and the safe mode option finally came up. I selected safe mode and it came up with a list of drivers then loaded to safe mode. In safe mode I restarted my computer and it went back into it's normal mode and it seems to be working great now :D *touch wood* :P if it happens again I will use your useful advice) Thanks Again