P5B wont recognise the hard drive

Since we can't see your system, please post the model numbers of *every* component of your system, including MB, power supply, CPU, CPU cooler, RAM, graphics card, case, etc. Also, please describe exactly how the drives are connected (e.g. for IDE, to middle or end connector on the cable, etc).
Also, please give more details on what you mean by "cant get the board to recognise the hard drive". Do you mean it doesn't show up in the BIOS main screen? Does the CDRW show up there?

The mobo is asus p5b
power supply 485 watt cooler giant
CPU 3.2Ghz Pentium 4 SL94X
Cpu Cooler standard Intel
Ram Corsair XMS2 1X2 Gb
Graphics card Nvidia 7300gt
Case non name
Hard Drive is connect to the middle IDE connector Set to master
CDRW is on the end of the IDE connector
The system starts with the P5B screen
Then goes to a screen with JMicron stuff and ST3250620A (hard drive) in green and says press any key.
Press any key and it has a blinking dash line

If what you mean by "P5B screen" is the main BIOS, that's what you'll have to go into to see what the BIOS is recognizing. Usually it says something like "hit DEL to enter BIOS".
Also, I would definitely put the hard drive on the end connector (master) and the CDRW on the middle connector.

Update: found this in a review of the board:
"It is very important to notice that the single ATA/133 port available on this motherboard is controlled by the JMicron chip, not by the chipset. This means that if you still have a parallel IDE optical drive it will only be recognized on Windows after you install JMicron%u2019s driver. The problem is that this driver comes on the motherboard CD-ROM, and you won%u2019t be able to install it, as the system does not recognize your optical drive. You can download the driver from the net, however the driver for the on-board LAN port is also on the CD-ROM%u2026 The only option you have is to copy the JMicron driver from the CD to a floppy disk or a USB pen drive using another PC. This problem happens not only with this motherboard from ASUS, but also with all other motherboards based on Intel P965 chipset we%u2019ve seen to date. Of course if you have a SATA optical drive you won%u2019t face this issue."

I bet that applies to a hard drive attached to the ATA port as well. This MB isn't really intended for people to attach IDE peripherals, so you might want to consider going with a different MB with better IDE support.

I have a P5B-Deluxe, maybe I can help.

I think the P5B screen the OP is referring to is the startup screen graphic that hides the POST info in the background. Mondo is correct, press the Delete key when this screen appears to go into BIOS setup. Under the Advanced Tab, make sure the JMicron controller is setup as IDE.

On the second screen after bootup that shows the Jmicron informaion, both hard drive and optical drive should be seen on this screen. Since you didn't mention your optical drive on that screen, that leads me to believe that it's the problem. Is the optical drive set as cable select? If that's the case, the end of the cable is telling the motherboard that it is Master, but your Hard drive is manually set to master and therefore there might be a conflict. Make sure your optical drive is jumpered to Slave.

Mondo, I haven't had any problems using optical drives on the Jmicron controller before drivers are installed. As long as it's set to IDE in BIOS, everything works fine. I don't know what that article you quoted is talking about really. If set to AHCI or RAID in BIOS, however, then you get problems until drivers are installed.

rw - I just saw that in a review that showed up in Googling the MB, so you may very well be right. Unfortunately Intel decided to phase out IDE support, so MB makers have been installing these JMicron controllers instead as a cheap alternative.