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Quadra 840av - Value of Crystal Y5
Posted by: RandomDamage on 2019-12-16 21:37:45
Hi all,

I'm troubleshooting a non-working 804av. The board was previously re-capped, but currently isn't giving a startup chime or doing much of anything when power is applied. 

Not sure if it is related or not, but the ATECS chip isn't providing any clock to the PSC. Digging further, it looks like crystal Y5 isn't working. Can anyone with an 840av verify what the frequency of this crystal might be? The part number on the can seems to be S011593-27 or maybe 5011593-27. So far, I haven't turned up anything on the web related to this possible part number.

Thanks!
Posted by: stormy on 2019-12-28 06:31:04
Hi all,

I'm troubleshooting a non-working 804av. The board was previously re-capped, but currently isn't giving a startup chime or doing much of anything when power is applied. 

Not sure if it is related or not, but the ATECS chip isn't providing any clock to the PSC. Digging further, it looks like crystal Y5 isn't working. Can anyone with an 840av verify what the frequency of this crystal might be? The part number on the can seems to be S011593-27 or maybe 5011593-27. So far, I haven't turned up anything on the web related to this possible part number.

Thanks!
I had my motherboard out today so I checked for you, this is what is printed on top:

SO115

93-44
Posted by: RandomDamage on 2019-12-29 20:05:50
Thanks! I did get the crystal to start functioning again. Not sure exactly what I did, but it seems to be working ok now. The frequency appears to be 16.38MHZ.
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