Memory Cache Problem 400 Mhz Sawtooth

[Lynn K. Persing]

G4 400 mhz AGP Sawtooth running OS 9.1

I think I've got big problems.  This morning when trying to reboot my 
computer after a crash, my boyfriend discovered this message on boot. 
"Apple's built-in memory test has discovered a problem with memory 
cache.  Please contact an Apple Service Technician."  It then 
proceeds to boot, I get my desktop, but then I get the message that 
the finder has unexpectedly quit and I should restart.  If I click 
restart, it goes into a finder loop again.  So I have to hit the 
button on the front of the machine.  And the whole flippin mess 
starts all over again.

So I tried a few things. Booting with extensions off, booting from a 
Tech Tool CD (it won't boot from any cd).  With extensions off, I got 
the same error message but it stayed running long enough for me to 
trash a bunch of system and finder prefs.  That didn't help.  I also 
ran the ROM (?) checker in Tech Tool and my L2 cache was not being 
recognized.

So, then I shut it all down and opened it up, and blew the dust out 
with some canned air.  I re-seated my RAM (which probably makes no 
difference at all since the problem is not with my RAM).  I hit the 
cuda button and started it up again.  I got the same message so I hit 
restart and this time it booted correctly and in Apple System 
Profiler my L2 cache is now recognized and it seems to be working ok. 
I'm guessing that I'm on borrowed time with this motherboard though.

Anyone else experience this?  Am I going to have to shell out bucks 
for a new computer?  Figures, the trusty ol' 6500 that I wanted to 
replace soon is still running like a charm.

I'm headed out of here today for a mini vacation in NH, so may not 
check back in until Tuesday for advice.  Any advice anyone has would 
be appreciated.  Really dreading shelling out the bucks for a new 
machine.  Maybe just a new motherboard?

Thanks,

Lynn