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HP Forum Archive 14

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HP9845B problem
Message #1 Posted by mirko on 17 Feb 2004, 9:04 a.m.

Hi,

I have a kind of problem with this machine. when I power it on the message "memory test in progress" appears. I had a look in the documentation and it says that it should disappear after a few seconds, but it doesn't. it stays on forever... roms are properly loaded (I believe...) any idea? thanks,

cheers,

mirko

      
Re: HP9845B problem
Message #2 Posted by Eric Smith on 17 Feb 2004, 11:06 a.m.,
in response to message #1 by mirko

I just got two more 9845Bs myself, and one of them does the same thing.

The other one runs for a few minutes than crashes. I think it's overheating. Maybe both of them are. I need to check the fans.

            
Re: HP9845B problem
Message #3 Posted by mirko on 18 Feb 2004, 4:19 a.m.,
in response to message #2 by Eric Smith

Please let me know whether overheating was the problem with yours. I'll check out mine tonight.

cheers

            
Re: HP9845B problem
Message #4 Posted by Petr Horský on 18 Feb 2004, 4:15 p.m.,
in response to message #2 by Eric Smith

Eric,

It may be interesting to swap their boards between them. Personally, I would start in the left card cage, with the LPU board.

Unfortunately my HP 9845B does exactly the same (I mean it remains frozen with "MEMORY TEST IN PROGRESS" on screen). My theory is, as the entire RAM (i.e. the leftmost boards) is accessible from both processors, perhaps it's the PPU (in the right card cage) who performs the whole memory test (this would also explain how come anything can be displayed at all), while the LPU may be completely faulty. To corroborate the theory, you can also withdraw the left ROM board (between the RAM and LPU). Obviously the LPU without its ROM is incapable of any testing -- and you still obtain a message on the screen, this time just a bit more cryptic.

I hope I will have another one here to attempt the board swapping within several weeks; perhaps I will learn more.

Anyway, I can hardly imagine any overheating after mere half a minute.

In case you succeeded isolating the trouble down to the board level, please let us know.

Regards,

Petr


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