You can try setting to legacy. I found this video. Did you set your BIOS setting to default before doing the install.
This video recommends setting to Legacy but if the disk was initialized as GPT using the convert GPT command I posted then Windows 7 64bit should be able to boot. This is 64bit Windows 7, correct?
Change the setting to Legacy and see if it boots. If not then you would need to do the following commands in diskpart because the disk has to be converted to MBR.
select disk 0
clean This will not zero the disk but simply delete all your existing partitions. It will be quick
convert MBR If you get an error ignore it
continue with the install.