I added a HDD to my core system last night. I ensured that the console was powered off and unplugged before I popped in the drive. On the initial boot, I got a single red light and an error code 67. When I cycled the power, all was well. I played Halo, Halo 2, Sega GT, and Forza Motorsport with no issues (aside from iffy framerates on the driving games). I then popped in PGR3 and played with no problems. I watched video, played Hexic, and ripped some music. Everything was operating smoothly.
This morning, I turned on the 360 and it gave an error code 67 again. In fact, if the console sits for more than 15 minutes, I get an error code 67 on the initial boot. If I cycle the power, everything is fine. When I remove the HDD, I get no error code. After the HDD is attached, I get the error when I first boot the system. Thereafter, no issues - unless I let it sit powered off for 15 minutes or more.
So, I believe the issue is in device discovery and validation. It has me wondering if the process the 360 uses to validate the HDD as a genuine peripheral takes so long that the 360 bails into a hardware failure message. OR, if the HDD takes too long to spin up before being validated that it causes the error.
Less likely is that it has something to do with the fact that I set up my user profile initially on the Memory Card. I copied everything over to the HDD and formatted the Memory Card to check this. On the second boot, it finds my profile and saves just fine. The console still exhibits the error without the Memory Card inserted.
If anyone else has encountered this, I would like to hear about it... especially if they have any solutions. My intent is to exchange the HDD for another (if I can find one). If this addresses the issue, I will post back here.
S7nn3r