ssd goes missing on uefi bios after indows 7 install

Hi
I have just bought a new bundle coolmaster Haf X case, asus 87-a motherboard uefi bios , intel i5 4670k 3.4 overclocked to 4.2 850w power supply nvidea gtx evga 780 and a 120 ocl solid state drive.

after formatting ssd from my old system and formatting and installing windows 7 my system booted up i installed mb drivers and grphics drivers without any problem but then on reboot my ssd suddenly disappeared from the bios leaving only my cd/dvd drive.
In ez bios there is a setting to see all sata ports and the ssd had completely gone the system booted up ok (still without the ssd showing in bios) but after several boots stopped; and would only goto the bios screen showing only my cd/dvd drive in boot options.
I reinstalled the system another couple of times and this continues to happen also in disk management (computer managemnt) the ssd now shows as being ntfs as in the first install it showed as efi

any advice would be a great help as i am now at a loss

Unplug all other HD's and peripherals,

Boot into BIOS setup, reset to defaults, save changes. Leave overclocking turned off. (If an EFI BIOS you'll need to decide if you want UEFI BIOS vs. Legacy BIOS. If UEFI follow these special steps for Install, otherwise enable Legacy BIOS or Compatibility Support Module to proceed with normal install.) Set DVD drive first to boot, HD second, set SATA controller to AHCI, Save changes and Exit.

Then boot into Windows 7 installer DVD or flash stick burned or written using tool and latest ISO for your licensed OS version here.

At first installer screen Press Shift + F10, or enter System Recovery Options to open a Command Box, type:

DISKPART
LIST DISK
SELECT DISK 0 (after confirming Windows 7 target HD #)
CLEAN
CREATE PARTITION PRIMARY
FORMAT FS=NTFS LABEL="WINDOWS 7"
ACTIVE
EXIT
EXIT

Next click Install Now, then Custom install to Clean Install Windows 7 to the partition you created. If it fails then report back at which step and the verbatim error message.

In addition read over these steps to understand the tools and methods which work best to get and maintain a perfect Clean Reinstall - Factory OEM Windows 7. The steps are the same for retail.

After install you can adjust partition size or Create new partitions for data, etc. in Disk Mgmt. You are creating the partition here for the purpose of wiping the HD and marking Active which overcomes certain install failures.

thanks Gregrocker
although i didn't turn off the over clock ( wasnt sure if i should as was adviced when i purchased it would un validate my warrenty ( its only 3 days old) )
I am using your your info on formatting and it is brilliant for my hdd which was being found but not being able to format using windows 7 instal disk (retail). though my ssd runs on uefi and so i've just found a tutorial on installs for that so am giving that a go hopefully all is going to go well
thanks again for your help i was at a total loss
will post back with results :)

The tutorial explaining the extra steps required to reinstall in UEFI mode is in my post above.

Sorry i think i did follow your link, and now everything is working perfectly am very happy. Your information was spot on
Thanks again

Great, Congratulations. Nice work!