Bad VRAM?

[Opry99er]

My daily driver is now sidelined. Power on, long beep---no boot. The 9919 is functioning, but is not getting reset at boot.

 

This is fairly common, I understand, but never on my systems. The last few months have seen 2 of my 3 consoles go inoperable due to this particular failure.

 

If I am recalling correctly, it is usually the case that one of the VRAM chips has gone bad.

 

 

I know this can also happen when a cart port shorts out or when the PSU goes bad.

 

Looking at ways of testing them now. Also pricing some DRAMs

 

 

Since I am down to one TI now, does anyone have a nice one they'd be willing to part with? I have some goodies for trade.

Edited July 31, 2016 by Opry99er

[Stuart]

I don't believe a bad VRAM will normally stop it booting to the menu screen (but that will be corrupted). Culprits for the long beep might be bad GROMs or GROMs need reseating, and IIRC someone recently found one of the scratchpad RAMs had gone bad, or a host of other potential failure points.

[00WReX]

Hello Opry99er,

 

I just recently fixed a couple of TI's and documented things a little under the following thread (Almost can be classed as a hijacking but I 'almost' managed to keep it on subject ).

 

There are some very helpful tips for VRAM troubleshooting provided by 'Lee Stewart' and 'mizapf'.

 

The second TI I fixed had a blank screen with a constant tone. This turned out to be one of the SRAM IC's.

 

http://atariage.com/forums/topic/254749-greasy-cartridge-port/

 

Shame you are not close by as I would gladly have a look for you. I recently purchased a cheap de-solder station and it works a treat.

I ended up removing and socketing 9 IC's while troubleshooting the second TI and all came out cleanly with no board / track damage at all.

 

Good luck.

 

Cheers,

Shane

Edited August 1, 2016 by 00WReX

[matthew180]

You can use the F18A to quickly test / rule out the DRAM.

 

I also have spare consoles. Send me a PM.

[Opry99er]

My third and final console went out under the same circumstances TONIGHT.

 

 

One, damn... It happens

 

Two, unlucky coincidence

 

Three..... In under a month???

 

 

 

Ideas, anyone? This makes no sense to me... What could be causing this carnage!?

[dphirschler]

I have some extras. One of them is bad. The rest are probably good.

 

Darryl

[sparkdrummer]

Owen

Have they all gone bad at your current residence?

If so, possibly spikes or lousy Ac current?

[RickyDean]

Have the Electric Co check your neutral line going into the house, I had a problem there once, where it blew out a TV and VCR,and the lights didn't work right.