Exception 6 Invalid Opcode; Sudden Death Evo D510??

Something very striking occurred that acted like a brand new hardware fault on my main/most best numero Uno Compaq that I depend on. JUst working away like any other afternoon and suddenly "OFF". Just a sudden "off" like you had shot the power supply. no warning, no hesitation, no unusual signs, no warning, just "off" in the blink of an eye. completely stone off like it had no power [but it did, protected by a good high-end surge protector]. all other powered devices ok. NIC phantom power light still on, monitor on, printer on, router/etc etc etc all on.

So I have a couple of so/so test thingies that can boot from so I put one of them in - a bootable PC Burnin package and I immediately got this sorta message as it tried to come up:
Exception 6 (Invalid Opcode):
followed by a long sequence of what appears to be memory location detail.

all attempts to boot that particular one failed.

I now have it running a Memtest on the "Ultimate Boot CD". I noticed as Ultimate boot was loading [linux kernel I presume] a split-second red message flashed and all I could catch with naked eye was "Failure"... and it went on with what it was doing.

so sounds like a sudden-death component failure that a driver hit that caused the original "black death".... am I right?

this is a Compaq/HP Evo D510 Minitower. no blockages no heat buildup to speak of.

any help would be greatly appreciated!!!
Anyone seen this before?

Last system I saw with random death syndrome like this was a Dell opti, finally tracking it down to a failing kbd controller onboard. but it took an unacceptable amount of labor to figure that out....

thx for any

Zapp

 

Did the RAMTEST run?

 

yes and no. the test was one of the converted russian-origin ones and its hard to discern how many of the routines completed. clearly SOME did, maybe all, returned no errors.
If you know of a better one to use, I am all ears!
at one time I had an old-fashioned pc-rack "BurnIn" test that would go for about 20 hours or so and exercise every component on the board, memory, cpu, cards but I have lost track of it. I'm mainly using the various tests packaged with the Ultimate Boot CD.. one of the recent images.