Hi Liz,
This might help you.
When you purchase your components, definitely buy a cheap power supply tester. There are many, Newegg has Powmax testers for around $15 at this posting time and I noticed that Aspire has one that is getting excellent reviews for less, including shipping. No, these are not "pro" voltage testers, but they will tell you if a rail is dead, or if it has fluctuating voltage, or the voltage is lower than it is supposed to be. Most of the time that is all you need.
Download the ISO of Memtest86+ and burn to a CD :
http://www.memtest.org/ When you are ready to start your build, do this:
*Take the empty case with the mounted power supply in it, plug in the power supply to the wall outlet, and then plug the mainboard cable coming out of the power supply into your new tester. Everything should register as good. Okay, now you know your PS is good.
*Next, take your new memory (RAM) sticks, put them in a different computer, insert your Memtest CD and let it run all night on your memory, or for at least two hours if that is not possible. Do one stick at a time. In the morning, if there is even one error message, that stick is bad. If so, you just saved yourself one of the biggest headaches there is, tracing a random BSOD crash resulting from faulty memory.
*The following applies only if you have a separate video card, not if you are using integrated video on the mobo: take your new card and insert it in a different computer. You do not have to install the drivers, just make sure that it will make contact and function and you get picture on the monitor. Okay, now you know that the card is good.
*Ground yourself by touching a water pipe, sink faucet, etc. Take the foam pad that your new mobo (mainboard) sits on in the box and place it on your workbench. Take the mobo out of the static bag and place it on top of the foam pad. Turn OFF the power switch on the rear of the power supply. Mount the CPU and heatsink/fan, insert the memory stick (use only one if you have two), and plug in your power supply to the mainboard.If you have a separate video card, mount it in the AGP or PCIe slot. Now plug in your monitor's VGA cable to your video-out. Make very sure that nothing that doesn't belong is touching the mainboard.
*NOTE*: lately these manufacturers have been getting very stingy with their power-supply cable-lengths. It may take a little positioning to get it to reach the mainboard power plug, so be imaginative. I created an extension to make it easy for myself.
Lastly, remove the silver, quarter-sized CMOS battery from the mobo and wait 20 minutes and then pop it back in. That resets the BIOS back to factory defaults just in case the settings got corrupted in handling.
Okay, show time! Make sure your monitor is plugged into a wall socket and turn on the power switch on the rear of the power supply. Now take a regular screwdriver, and cross the two, tiny contacts on the mobo (if you don't know where they are, use the mainboard manual to locate them) that the on/off switch from the front of the case plugs into. The computer will start, the CPU fan will spin up. You should see the POST screen on the monitor. Great! Everything works that is the foundation of your computer!
If it will not post, you know for sure that it is one of the components that you just installed, and troubleshooting is SO-O-O-O much easier.
In addition to the above, you will notice how MUCH easier it is to mount the CPU and heatsink/fan before you install the board inside the case!
At first you may get an anxious feeling about having the mobo sitting naked on the workbench. Don't worry about it.
Trust me, the above will save you countless hours of headscratching trying to find what of the many components is causing problems after the whole computer is installed. Just ask any of our posters who are having problems trying to get their new-builds to boot!
Let us know if this helps !!
Building pc - help needed 
Linear Mode
