alright this is a mining hardware mystery for someone to prove they are smarter than I am. ( like thats hard right?
I like to consider I have mastered the art of the 5 x 5870 windows mining rig, in fact I have 5 of them.
but this one rig , this one little snot nosed, evil, cablepair mocking rig has a very strange problem
on all my 5870 rigs I clock the cards at 950 core, this gets me about 430 mhash per card
the rig in question will only allow me to clock 4 of the cards at 950 and the 5th one has to be clocked at 800
but it doesnt have to be the fifth one, it could be anyone, infact 4 x 950 and 1 x 850 core is the limit, I can clock them all lower and the system will run fine..
Someone is going to say "You dont have enough power!" Thats what I thought at first as well, at first I had a Rosewill 1000watt 80 plus , which should be enough power, I thought maybe there was something wrong with the PSU and it was not putting out enough power, at that
time if I clocked the cards too high as described above it would just shut off
so I switched the PSU to a corsair HX1000 80 plus a PSU i knew for a fact could power 5 x 5870 because it is on my other rigs,
sure enough I run into problem clocking it higher than describe above except this time its really strange, instead of just shutting off it will mine for a min and then all of the sudden one of the GPUs will display 127.5 C and 0 RPM in cgminer
how weird is that ? Every single time it shows 127.5 C and 0 RPM in cgminer
exactly 127.5 degrees c, also it is not the GPU it self, I have swapped out all the GPUs with others that I know work, I have moved them around, I even changed out the motherboard with another one, as well as formatted reinstalled windows so I know its not a software issue.
to recap here's a break down
5 x 5870s
you cant clock them higher than 4 x 950 core + 1 x 800 core
if you do the system crashes after mining for a min
with Rosewill PSU it just shuts off
with Corsair PSU it shows exactly 127.5 c 0 RPM on one gpu then freezes
to try and find the problem I have
Swapped PSUS (with PSUS that are known to be working and have enough power)
Formatted / Reinstalled - Ruled out Software Problem
Even tried not using a particular PCI-E slot that the problem occured on before , it just moves to a different GPU on a diff PCI-E
Could the CPU be doing this?
I mean really whats left to rule out
CPU, Ram, PCI-E Extender Cables, those are the only variables left. and none of them make any sense to me,
Has anyone ever heard of this problem? Have any clues as to what could be causing it? I have been racking my brain trying to figure it out and I cant for the life of me.
Thanks for taking the time to read this!!!!