newbie just bought 6 280x miner with some problems

[eeaweeaws]

I spend about 3 hours but still can't fix it
The MB is h81 btc pro
But it can only use 5 cards to mine
The sixth card can't even detect in windows
But when I opened gpuz,it said its running in 6 cards..why?

Also,when I got more than 3 cards
One of the hash rate will be extremely low,I can sure they are using the same settings

Please help

[bluemist]

I had the same problem with 6 7950s. You'll most likely need to do a presence short - see this thread:

https://bitcointalk.org/index.php?topic=102547.0

[eeaweeaws]

I had the same problem with 6 7950s. You'll most likely need to do a presence short - see this thread:

https://bitcointalk.org/index.php?topic=102547.0

THX BRO but that problem is soloved.
now the only problem is why it cant mine with 6x 280x..

[eeaweeaws]

and somthing interesting is when i open cgminer
all 6 cards run at the same time,but just 5 is detected.

[fatguyyyyy]

So is the 5 at least mining?

This just makes me not want to get into alt mining.

[eeaweeaws]

So is the 5 at least mining?

This just makes me not want to get into alt mining.

yeah the 5 is mining
but dont know why the sixth cant detect..

anyway i think its still worth to get into alt mining right now

[Colin Miner]

Try the 6th card on its own, so its running as one card only.

If it doesn't detect, the card is dead. If it works, then the card is good and you need to look at something else.

Is the power supply up to the job? Try a multimeter on the PSU to see the 12v is really 12v etc.

[eeaweeaws]

Try the 6th card on its own, so its running as one card only.

If it doesn't detect, the card is dead. If it works, then the card is good and you need to look at something else.

Is the power supply up to the job? Try a multimeter on the PSU to see the 12v is really 12v etc.

i test every single card before i put them together so i can ensure that card is okay..
power supply up to the job for sure too