Bootcamp Windows 7 installation, USB is not recognized only on bootloader
I attach answer here as you guys suggested.

SOLVED - Bootcamp Windows 7 installation without USB, ODD

OK, I'll explain how I worked it. I followed almost of all of David's method here and here, but there are little differences.

Before we start, please note that I'm using MacPro4,1 which does not support USB installation of boot camp and I detached ODD. Instead, I attached another HDD in Bay 2.


You need rEFInd, VirtualBox, NTFS support for OS X (like Paragon or NTFS-3G), a bootable Windows installation ISO.
Service Pack applied ISO is also ok.
Update Mac firmware as recent one as possible. here
Open Boot Camp Assistant and download driver files into any usb.
(Just 2nd option of 3 of boot camp. if your boot camp assistant does
not have 3 options, it would be 1st option)
install NTFS support for OS X, rEFInd and VirtualBox.
Format a partition with MS-DOS(FAT) which is going to install
Windows.


I recommend you not to use Boot Camp Assistant app to format. Use Disk Utility instead.

In terminal, type diskutil list and remember disk and partition
number of target partition. In this example, I use disk 1 and
partition 1. So, disk1s1
Unmount partition and set permission.

diskutil unmount /dev/disk1s1

sudo chmod 777 /dev/disk1s1

Create VirtualBox image with raw disk access. anywhere except
bootcamp partition

sudo vboxmanage internalcommands createrawvmdk -filename bootcamp.vmdk -rawdisk /dev/disk1 -partitions 1

sudo chown $USER bootcamp*.vmdk

Open VirtualBox and create a VM. Just set disk as what you already
made, and ISO file of windows installation.
Start VM and install as normally, BUT when you get in 'setting
 computer name' phase, shutdown VM forcibly.
Turn off VirtualBox, and delete all files in the boot camp 
 partition (including BOOT folder and bootmgr file - If you can not 
 find them in Finder, use terminal to delete them or change Finder 
 option with defaults write com.apple.Finder AppleShowAllFiles YES)

Of course, Before open finder, mount partition first.
 (If you didn't installed NTFS support, you can't mount or delete file)

diskutil mount /dev/disk1s1

double click windows ISO and copy all of the item into boot camp
 partition
Reboot Mac and in rEFInd bootloader, select 'Windows NTFS volume'
Install windows again, but DO NOT format boot camp partition.
Installation is finished. When you see desktop, install Boot Camp
 Driver which you downloaded at Step 3
After boot camp driver is installed &amp; if you can see 'Windows' on OS X boot loader (which you can enter by pressing alt/option), you don't need rEFInd anymore. You can delete it in OS X.
You will see bootup selection between 'Windows 7' and 'Windows Setup' when booting Windows. If you don't want to see it,
Go to Control Panel - System - Advanced Settings - Advanced tab - Click Setting button which lies on 'Startup and Restore' section - Uncheck first one.