custom pc builds:no boot trying to boot from usb.

[orphanslayer]

 my computer wont boot up. every time i try and boot it goes straight to the screen where it says verifying dmi pool data.......
amd data change...... update new data to dmi! and it gets stuck there and wont go past. i am trying to install windows 7 of of a flash drive but that wont boot up. i have gone into the settings and set it to boot the usb drive but no luck still same message. i have even tried resetting the cmos but no luck.
system specs:
motherboard is a Gigabyte 78LMT-S2 Micro ATX form factor with an AM3+ socket. Cpu is an AMD Athlon II x3 with an unlocked 4th core (for some reason, when I unlocked the 4th core, it reads it as a Phenom II). Graphics is a Radeon R7 260x which is the special edition from best buy, which just means it has dual fans. RAM is a 2x4 gig set of gskill ripjawsX with a total of 8 gigs. Power supply is a Corsair CX500M which is an 80 plus bronze rated supply running at 500 watts.

[Geek-9pm]

The specs look good. But what is the history of this PC?
Did it once have another system? Which?
The reason I ask is because some versions of Linux may mess with the disk in a way that makes in impossible to start up Windows install.

If you have another PC, try making a DVD with he Windows 7 ISO. And please tell us how you  got the ISO?  Did you buy it from Microsoft?
There is the possibility that either the USB stick is bad or the ISO image is bad.

Is this the method you used?
You Tube Video - Windows 7 from USB
With more details, you can get more specific answers.

[patio]

Replace the CMOS battery with all power unplugged...

[orphanslayer]

the pc has always had windows 7 i got it from a friend who built it from scratch and the iso on the usb i got from the windows installation disk i used wintoflash to make a bootable usb drive and this pc has no disk drive or floppy which is why im trying to boot from a flash.

[patio]

Windows won't boot from an external device...

Invest in a HDD if you wanna run Windows.

[Salmon Trout]

I think the OP has made a bootable USB stick with a Windows installer image on it. This issue can be caused by:

Bootable drive not correctly created or corrupt

Boot settings in BIOS not correct.

(and others)

http://www.computerhope.com/issues/ch000474.htm