Are risers causing problem?

[vengeance]

Running 3 5870's, 2 on 16x risers and 1 on 4x to 16x riser. PC will just freeze after random amounts of time mining, then i have 2 reset.
It can run a couple of hours no problem, sometimes couple of days. If I remove the card on the 4x to 16x riser and just run the 2 on the 16x risers, same story.
If i remove the risers and run the 2 straight on the m/board no problems. Ruled out power problems. So it must be the risers. But why? Could it be EMI from the risers?
Just want everything to run smoothly in 1 rig.

[sadpandatech]

Running 3 5870's, 2 on 16x risers and 1 on 4x to 16x riser. PC will just freeze after random amounts of time mining, then i have 2 reset.
It can run a couple of hours no problem, sometimes couple of days. If I remove the card on the 4x to 16x riser and just run the 2 on the 16x risers, same story.
If i remove the risers and run the 2 straight on the m/board no problems. Ruled out power problems. So it must be the risers. But why? Could it be EMI from the risers?
Just want everything to run smoothly in 1 rig.

  It is possible the risers could be slightly defective.
  It is possible the risers are blocking some fo the airflow and the cards are running just enough hotter to cause issues.
  It is possible the mobo is having issues pushing the juice pulled from board up the risers. (try some with power molex to test)
  It is possible that baby jesus hates your tree killing endeavour and is stopping it. ;p

  What OS ver and kernel (32 or 64 bit)?
  What ver Catalyst drivers?
  What miner ver and kernel ver??
  Have you inspected the riser cables closely for any loose connections or shorted connections from poor soder?

[ocminer]

Make sure the rises are firmly inserted/well seated into the mobo pcie slot, I had a similar issue where it was a contact problem. A firm insertion and some hot glue fixed my problems.

[bulanula]

Make sure the rises are firmly inserted/well seated into the mobo pcie slot, I had a similar issue where it was a contact problem. A firm insertion and some hot glue fixed my problems.

LOL hot glue on a mobo Do not want

[likuidxd]

A firm insertion always fixes the problem

[tritium]

are you overclocking the cards? i have had it where they will run for a day or 2 and then fail, lowering the clockspeed by 10mhz solved it

[likuidxd]

are you overclocking the cards? i have had it where they will run for a day or 2 and then fail, lowering the clockspeed by 10mhz solved it

This just sounds like a heat problem. The card will lower it's clocks to preserve itself

[buzdowan]

Maybe even power issue, check your psu and 12v condition.

[ocminer]

hot glue on the pcie slot/riser is absolutely no problem as long as you dont use lots of it..

a little spot is enough to hold the riser in place and this little spot can be removed easily without any damage

[P4man]

LOL hot glue on a mobo Do not want

hotglue is plastic. Its non conductive. And you can always remove it. Its perfect for stuff like that, or for fixing GPU ram heatsinks that otherwise fall off (putting the glue on the sides obviously as its also a very poor themal conductor). Hot glue and duct tape will let you fix almost anything

[cicada]

.. or for fixing GPU ram heatsinks that otherwise fall off (putting the glue on the sides obviously as its also a very poor themal conductor).

Careful with that one, hot glue tends to melt when it gets hot

I'd agree it's uber useful in the electronics world, I don't know how many PSU's I've cracked open to see what looks like someone just poured it in to keep everything in place.

For the heatsink problem, I'd highly recommend thermal adhesive instead, as that's kinda what it's meant for

[P4man]

Careful with that one, hot glue tends to melt when it gets hot

High temp hot glue melts at ~200C Low temperature hot glue melts at ~120C. RAM chips and heatsinks shouldnt get anywhere near that hot. In fact for the most part you can do without ram heatsinks at all, provided you have a fan blowing on them and not watercooling. RAM chips will start failing at ~70C. If your hot glue melts, you have other problems.