No signed device drivers were found.

Load Driver.
No signed device drivers were found. Make sure that the installation media contains the correct drivers, and then click OK.

I just installed a new HDD.
Specs:
Hitachi
500GB
P/N: 0F15629
S/N: JE3VM9HK
MLC: JPT50E
FW: 50E
LBA: 976. 773. 168 SECTORS
CHS: 16383/16/63
RATED: 5V 450mA.12V 700mA
SATA: 6.0 Gb/s
RPM: 7200RPM
HDS721050CLA662
Type: DS7SAC500
C P/N: H3D5001672S

I installed the HDD on a working PC with Windows 7 64bit and went into Computer Management and formatted the HDD and add a simple volume and works fine.

Put back into the new PC installing Windows 7 64bit and this error of not finding the HDD?

Please help.

Put back into the new PC installing Windows 7 64bit

For better help with problems, Can you post your NEW specs.
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Just to clarify, my 2nd last line means I have put the formatted HDD back into the new PC.
I then run the Windows 7 64bit installation DVD and the error still occurs:
Load Driver.
No signed device drivers were found. Make sure that the installation media contains the correct drivers, and then click OK.

Please help.

So your NEW PC is a old 32 bit P4, yes.

The CPU is fine.
I reinstalled with another downloaded DVD of Windows 7 64bit and the HDD was recognised.
All fixed.