March 2009 Software Updates for C4580

Question

I only have two problems left with my printer:  (1) it loses its connection if you don't print for a while and (2) it becomes unresponsive if you don't print for a while.  The only way to cure either issue is to restart my whole system including modem and routers, unplugging the printer and leaving it unplugged for at least 5 minutes (if I don't, it turns on automatically when I plug it in, and it is still unresponsive).
I was delighted to see the patches - I had read that the one to cure the unresponsiveness was due out in March.  Here's the problem:  I can't install either one of them!  When I look up the drivers for my specific printer, both of these are listed.  The one to correct the connection loss says that I don't have the right device so I don't need the update.  The one to correct unresponsiveness insists that my printer is not connected...even though it is and is printing just fine.
I don't understand in the first case if the driver is listed under my model why I am blocked from download, and in the second case why it can't seem to "find" my printer.  As an attempt around this, I ran my HP Update software and it did download an update xx.xx.12 (I don't remember the first part!).  So, I'm wondering if those fixes were in the update - does anyone know if there is a way to find out?  I've searched everywhere to try to find out.  And if not, does anyone have any experience with these patches that might be able to help me troubleshoot?  I'm out of ideas.
Thank you very much for your time!!!

Answer 1

The saga continues. The iMac would not restart after either a shutdown, restart, or sleep cycle. I opened it back up, removed and replaced the RAM, and it started fine. But would not restart - just a black screen, no startup chime, and 100% fan speed.
I removed the back and put it right back on - no other hardware changes. Same sequence: good first boot, failed subsequent boots.
I unscrewed the back, DIDN'T move it AT ALL, screwed it back together, and same sequence: good first boot. Very strange. The iMac must have a continuity check that involves the three screws. When the screws get backed out, the circuit must get broken and trigger something.
So I ran the OS X 10.5.2 combo updater over top of the existing 10.5.2 install. After the install was complete, I got a little message that said the computer needed to update Boot Cache files and restart. Crossing my fingers, I clicked OK.
So far no problems. My guess is that there is a hardware override of boot cache after the case is opened. Then on subsequent reboots without a hardware config change (actual or assumed by a screw movement), the system looks for the boot cache. The recent updates corrupted those files or something in the process, making the mac hang. By over-installing the combo update, I forced the boot caches into a usable format again.
The phantom part is shown in this photo. (Right click and open in new window to see bigger). The offending part and gapping are both on the power button and peripheral port side of the computer (left when viewed from the back). It looks like a printed circuit board held on by a hard drive mounting screw: .
The right side is perfectly flush as it's supposed to be. The case warping on the left side is shown in this photo: .
Any thoughts?