Topic: Mining Hardware Mistery [127.5 C / 0 RPM] - page 2. (Read 2724 times)

no im not using powered extenders the way I do it is I have two cards sitting directly on the motherboard and 3 cards via extenders

your making a logical argument but this is what bothers me about it.

I have 5 rigs, they all have the EXACT same setup, same motherboard, same cpu, same gpus same psus, even the same exact brand names

If I can replicate the same configuration 4 times and it works perfectly with no problems (and has been working for many months) the 5th one should be able to work the same way too, unless there is some sort of hard ware problem.

I even swapped out the motherboard with a spare brand new gd70 I had for backup, I am starting to lean towards some sort of problem with one of the pcie extenders

I dont think 925 x 5 will work, I tested several different setups just to keep the thing mining while I troubleshoot it and I determined the best way to keep it going and maintain the highest speed possible was just to lower one single card down to 800 and keep the other 4 at 950

I tried multiple times lowering every single card by a little bit and when I lowered it down enough to where it would be stable I lost more mhash then just doing it the way previously described.

I am going to order some new pcie cables today, maybe I will get one with a molex connector just for fun

Thats not my point. It would be worth checking if 5x925 MHz works on your troublesome rig or not. Power consumption of that is higher than 4x950 + 1x800, if it works, it would make power delivery issues with the motherboard far less likely. If 5x925 does not work, thats what I would betting on: too much power pulled from the PCIe bus. Are you using powered extenders?

its not a problem where I am trying to clock them too high, I have 5 rigs that are exactly the same

same gpus, same motherboard, same cpu, same psu, same everything

i clock them all at 950/180 with no problem, I have been mining with 5870s for almost a year I know exactly how to clock them

Have you tried 5x900 or 5x925MHz?

GPU Caps Viewer reports 127.5c when my GPU's are subzero (HWInfo64 and trixx reports it correctly with a - sign), but thats probably not the case for you.

thats an interesting idea, those extender cables are pretty chincy , I have had to resolder serveral of them , they are super fragile

what boggles my mind is where the heck does the 127.5 c and 0 RPM come from? why that exact reading which is of course completely incorrect, if you look at the gpu thats giving that reading the fan is spinning fine and the card is not hot to the touch

I've had issues with pci-e ribbon cables; it's really cold here in wisconsin and I have a miner outside. I had one GPU causing system freezes whenever a load was applied to it. Figures that it was the PCI-E cable. I switched it with another and it worked fine after. When I brought the cable inside, 1 of the wires had disconnected from the pcb. I tried investigated where exactly it disconnected and a bunch more wires ripped off the pcb. Gotta love that chinese quality.

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)
swapped Motherboard
Swapped GPUS
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

Whats Left?
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!!!!