2007-05-01

K7S5A Back From The Dead

My little ECS K7S5A has been a rock solid little board all these years. It's getting to be a bit long in the caps, at almost 6 years old, but it's been good to me.

Until, of course, for reasons apparent to many of you reading this, I needed to edit the DMI info. One toasted board, served on a nice bed of silicon.

For other folks who manage to get to this point (and there are some, since I looked about for a solution for my problem and didn't find one), here's the answer for resuscitation.

Symptoms:
On POST, wicked green screen with pink and yellow streaks --- hit TAB key. Enjoy your normal POST view until you get:
DMA Error
System Halted

Quake in fear. At this point, setting the clear CMOS won't work, nor removing the CMOS battery. Yanking out the nice little winbond chip doesn't do much either. If you have a way of hot flashing, you might be shiny at this point, but, then, who wants to troll e-bay in the hope there's a broken one somewhere that you can cannibalize? Whatever; no point in waiting, either.

Make your AMIBOOT.ROM floppy as usual (you DID keep a non-USB floppy around somewhere, right?) and pop it in the system. Turn system on.

With a flatblade screwdriver and a steady hand, short out pins 30 and 31 (A17 and #WE) on your DIP winbond chip. (If you've got the other kind, sorry, no idea if this'll fly --- it still might). (Note: You can probably use other pins as well --- the goal here is to screw things up enough that the BIOS decides it needs to invoke the boot block).

System should beep once, with no display, and floppy drive should start reading. You're not out of the woods at this point; go ahead and stop shorting the pins, and wait a minute or two.

Now, power off system, hold CTRL-HOME, power on system. Floppy drive should be reading, and you can release keys. Listen for the 3 beeps, wait until floppy drive is done, and watch system become useable again.

Woot.

I can't take credit for this solution. A far smarter relation suggested it on the phone, and, I might add, had a little disappointment in his voice when he assured me I wouldn't electrocute myself.

This trick may works for other motherboards that have a boot block that isn't modified during a flash.

For info on the flash chip in the k7s5a, google-fu for the win: w49f002u.pdf.

(This was originally posted on my now defunct Myspace blog.)