@naimaier My cards crash with that OC i think they dont like the SOC Freq and Soc VDD …
Trying @JustifiedMX Oc seems to downpower compsumption to 40w but Vram Still Hot , seems like the problem is what @HybridJAP posted will need to open the card and take a look on the thermalpads …
Thnx a lot for all comments and help!
Hi @Hilbe, can you post a pic of your HiveOS screen and OCs buddy?
Straight off the bat I would suggest raising SOCVDDMax and Core Voltage by +5mV intervals until the crashing stops. I just had to raise both by +5mV on one of my Powercolors after putting it on a PCIE Splitter so I feel your pain 
OK, it can happen, the best thing to do is test diferent configurations! all we achive is part of a hardwork trying diferent OC and understanding how the GPU runs with each Freq or Voltage
Lot of depends on used miner. I decided to use TeamRedMiner little less MH, less W but stable. 3th card is unstable so I had to use different settings.
I just found a realy nice video about the RX 6600 on youtube:
I added 3 more ASUS RX 6600 to my rig. Before it was rock stable. Now i cant get it running well again.
I tried your numbers and even set the SoC Freq. to 534 and the Mem.Freq. to 900 on GPU 6.
Still, i get:
What i noticed from the start, is that this card reports lower temps (and is cooler? idk)
Any ideas?
Tips?
Hi @haenno, is the rig stable without OCs? (always worth checking after adding new GPUs if you have problems, it rules out bad OCs and also checks if hardware & power are working ok and you don’t have any PCIe lane issues). Be aware your power consumption will increase substantially with no OCs so double check your PSU and PCIe cables have sufficient power capacity.
Also you can try removing the SoC settings (Freq & VVDmax) for GPU6 and see if it is stable then start to reduce. The hashrate for GPU6 is quite low, it might just be silicon lottery or it might point to something else the rig is not happy about.
Finally seem to have got my rig stable after adding a 4th XFX 6600 (which bizzarely caused GPU1 to crash the rig every 24 hours for 10 days) 
I might wait for a few more days uptime then go back to the Asus 6600XTs and see if I can get a better hashrate/wattage out of them.
Hi @Batfink, thank you for your reply! I reset to your default values and try it for GPU6 w/o the SoC Freq.+VDD. Will report later… 
Thanks a lot!
Has anyone had random offline times here? No miner faults just a time period in where you 6600 rig just goes down? Trying to collect some data if you did.
which miner? use TRM and all will be fine or at least it will show the problem card.
My latest setup. Works 2-3 days without issues and reboots only because I still have to use WiFi (waiting for parts).
Anyone here doing dual mining on these cards? I haven’t had the balls yet to mess with my settings to get TON dialed in. Think the wattage would go up a lot.
Wow! I’m not alone. That’s good and bad news LOL. I was blaming the Wi-Fi but now we have LAN cable up and running so it’s not related.
So far: I did wipe out all the overclock and removed the flight sheet and re-do it again. I removed AutoFan and turned off Watchdog - the same issues randomly go “frozen”. Put them back since it’s not resolving my prob.
If you just plug in the screen it shows nothing. Just the last part where it got stuck. When you push the power button it does nothing (when it should shutdown). The only solution is to “hard-reboot” every day.
Need some help here! The worst part is it keeps draining electricity for nothing when it’s “frozen” and I’m not sure what to do next. It has two 850w EVGA PSU and chip to sync them but I don’t think this is the issue. IDK where to get any clues/logs of something to find out what’s the issue.
