I am currently at work and the computer I normally use won't boot up, it is windows 8.1 and when I turn on the computer once it hits the windows logo it turns off after a second or two. Tried hitting F8 before the logo but it doesn't take me to advanced settings or anything.

Any ideas or suggestions to try?

Could be anything, but I think the two most likely big ones would be a bad PSU or an overheating CPU. I'd do a quick visual inspection and make sure everything is seated properly, and that the CPU heatsink isn't dangling off and the fan is actually spinning when you power the computer on. Beyond that, you could try reseating RAM sticks and disconnecting unnecessary devices and seeing if there is any change.

You could also try resetting the CMOS just in case but unless you're familiar with the motherboard it may not be evident where the jumper or switch is.

If you feel comfortable opening the side of the case up. You could check if the CPU fan is spinning, might be overheating and then shutting it self down. Same goes for the graphics card. As MB mentioned it might also be the power supply giving up.

There is also the possibility that it might be that one of the harddrive connectors are not all the way in, or that it has bad sectors, though usually windows is smart enough to detect when something is wrong with the drive and perform a check disk on it. But really it could be anything, thats the worst part about troubleshooting a PC.

Unfortunately with Windows 8 they decided that you don't need to be able to get to safe mode simply so F8 doesn't work. It actually takes a ridiculous amount of effort to get to safe mode on Windows 8- and it seems you can only do this if the computer actually boots up in the first place. It's annoying, but not actually anyones fault. You see it doesn't work... because your computer is too fast and the way they designed Windows 8 to boot unless you have a slow computer it doesn't have time to see you even input a keystroke before the OS has started opening.

There are ways to hack it, but I don't recommend it.

Anyway, like MB said check the individual pieces of hardware and make sure it's plugged in. Blow out your case. I know it's obvious, but you never know... make sure you clean any dust off the heatsink (assuming you have one and it's not liquid cooling or something).

If you have a recovery or repair disc you can try running that (people often think they don't need one, so they ignore making one, but cases like this are reasons why it's important).

If everything is in place, and it still doesn't boot up, or the repair/recovery doesn't work, something could need replacement or reinstallation. That is the last case scenario, but worth noting in case it happens (I hope it doesn't, that more than sucks when that happens).

I am a fan of using "live" versions of Linux that can be booted off of USB or CD for diagnostics. If you are familiar with modern Linux, this is really easy to do and offers a way to access and inspect the hardware to see if it is functioning correctly where importantly there are tools built to access SMART status of any drive that supports it. Once you've either confirmed or eliminated hardware problems as an issue you can go forward with fixing up your install with a rescue disk or whatever you need.

cpu temps should be able to be viewed in bios as well, if you can access that.