Macbook doesn't recognize new or old HD

I own a macbook from 2006 running 10.4.11 Tiger. The other day I got the flashing notebook question mark, so I ran installation and it wasn't showing up in disk utility. So I installed a new HD.

It is the Seagate Momentus 320GB 7200 RPM 16MB Cache 2.5" SATA 3.0Gb/s Internal Notebook Hard Drive -Bare Drive.

After running the OS X installation disc again, my new hard drive did not show up either. I am confident that I seated it correctly, and it should be showing up. Where might the problem be, gents? Is it in the SATA connection, the Logic board, or what? Any help would be appreciated. I'm going to go buy enclosure to see if the original HD is, in fact, sill good.

If you did everything as you say and the new hard drive is not being seen by Disk Utility, then it could be the SATA controller on the logic board. Let us know if the old hard drive or the new one works OK from an external carrier. If your old hard drive is OK, you may be able to boot with it using the external carrier.

And BTW, please don't post twice. I deleted your second post which was a duplicate of this one.

Regards.