If the memory passed the memtest86 then how could it be suspect?

Easy... when the test was being run, the disks were idle, and any power fluctuations they might cause when accessed not present.

 

All it would take is one bit in the RAM to be voltage sensitive... and there goes your parity calculations...  As I've said earlier, it is a process of elimination.  The other thread I was helping with had a disk controller card with two ports.  Each port worked fine individually.  When simultaneous requests were made to the two disks, errors resulted in the data being read, resulting in occasional random parity errors.  The disk controller fault might be perfectly fine in most PCs, but not in one where both disks would be active at the same time.  Again, he does not know if the card was voltage sensitive, of it was "crosstalk" on the card from one port to the other, he really did not care.  He knows he does not want that card in his server and replaced it.

Hmm.  I am trading out the memory chips.  Is it a valid test to do a parity check up to 5% or so (I'm seeing sync errors), swap out the chip and try two parity checks up to the 5% and if there are sync errors on the second check then keep swapping out?  Or do I have to do a complete Parity-Sync and parity check each time?

 

Also, I am monitoring the Watts via a KillAWatt device.

Hmm.  I am trading out the memory chips.  Is it a valid test to do a parity check up to 5% or so (I'm seeing sync errors), swap out the chip and try two parity checks up to the 5% and if there are sync errors on the second check then keep swapping out?  Or do I have to do a complete Parity-Sync and parity check each time?

Yes, that is a valid test.  If it was memory related, and you did fix it by replacing a strip, the first parity sync (up to 5%) would correct any issues, the second should not find any (in the first 4.9%)

I tried 3 different memory chips.  Same result, sync errors.  I also disconnected disk1 so it's not drawing power.  That leaves just two drives in the system with each one on a different 12 volt rail.  Same result, sync errors.  Now what?

I tried 3 different memory chips.  Same result, sync errors.  I also disconnected disk1 so it's not drawing power.  That leaves just two drives in the system with each one on a different 12 volt rail.  Same result, sync errors.  Now what?

Well, it sounds as if you are using a process of elimination...

 

It does not sound like it is either disk

It does not sound like it is the memory (passes memtest, and you've tried alternative memory)

 

Are you still using this 4-port SATA adapter? http://www.monoprice.com/products/product.asp?c_id=104&cp_id=10407&cs_id=1040702&p_id=2667&seq=1&format=2

 

If so, do you have the older 2 port SATA adapter you started with?  If yes, you might try removing the 4-port temporarily, putting in the 2 port, and do the same experiment on a single data drive and the parity drive.  You might need to use the "devices" page to put the disks on the correct logical assignments in unRAID, but this test will eliminate the 4-port card from being a possibility if it still has difficulty calculating consistent parity  (you can repeat the 5% tests, no need to do a complete parity calc).

 

Joe L. 

 

There's just no more fun left in that machine.  It's a SV25 xpc and to replace the sata card means tearing down the entire machine to get at it.  I'm going to think about whether I can get interested in making a different unraid machine.  If anyone has an unused really cheap motherboard or combo MB/cpu/RAM that they know works with Unraid then let me know.  I guess the idea is it has to be on the linux-compatible list to work.

 

 

I did some checking on the hardware list.  I'm considering this motherboard and cpu.  I already have a case, psu and some extra ddr2800 ram.

 

Any thoughts or suggestions?

 

Motherboard:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813128342

Cpu:

http://www.newegg.com/Product/Product.aspx?Item=N82E16819103698

 

edit:  I ordered those two parts today.  Thanks for helping with my older machine's issues.  It quit booting today after taking it all apart again.

I did some checking on the hardware list.  I'm considering this motherboard and cpu.  I already have a case, psu and some extra ddr2800 ram.

 

Any thoughts or suggestions?

 

Motherboard:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813128342

Cpu:

http://www.newegg.com/Product/Product.aspx?Item=N82E16819103698

 

edit:  I ordered those two parts today.  Thanks for helping with my older machine's issues.  It quit booting today after taking it all apart again.

Your old disks data will still be there when you assign them in your new MB config..  At least the data will be there.  I agree with you, it stops being fun when the hardware is fighting you.

 

Joe L.