Post
Topic
Board Mining (Altcoins)
Re: Performance difference from one brand of reference r9 290 to another?
by
hodger
on 10/01/2014, 15:16:50 UTC
I got a bunch of PowerColor R9 290 cards, and noticed they run best at a engine/mem ratio of ~0.74. You could probably get higher than 800 if you kept that ratio, but overclocked a little bit.

All my settings run at Powertune @ +20
1105/1500 gets me 855
1075/1450 gets me 835
1050/1400 gets me 810
1025/1350 gets me 795

I would love to run them at 850+ each, but the temps are too high for my liking right now, so I have to downclock. We're going to move them in a couple of weeks and install some more AC units. Hopefully between that and 2 weeks of burn in will allow us to overclock even further.

Quick question....Is this at stock voltage?
Yes, stock voltage. I'm in linux, so I can't adjust that at all.

Thanks for confirming, wanted to check as I'm on Ubuntu too, and while it's theoretically possibly to change firmware and change voltage, it's something I'd rather avoid.

One thing that did occur to me once I'd found a happy setting last night, is whether the extra 30watts per card is likely to have a negative effect on the mother board.  This rig is cased up for numerous reasons, so I'm not using powered risers...It's a decent 1300w EVGA PSU so I have no concern with the PSU itself as at most the system is pulling around 1050w at the wall.  I gather 6 pin power is rated at 75w and 8 pin at 150w, but wasn't sure whether "rated" meant "maximum" or whether a decent PSU would supply more, or whether anything over 225w will definitely be coming from the motherboard?

So far the system seems happy, but it was just something I curious about:

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 (5s):2.421M (avg):2.370Mh/s | A:737280  R:19968  HW:0  WU:2166.7/m
 ST: 2  SS: 6  NB: 498  LW: 5323  GF: 1  RF: 0
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 GPU 0:  87.0C 3928RPM | 792.9K/785.4Kh/s | A:233984 R:6656 HW:0 WU: 689.0/m I:20
 GPU 1:  89.0C 3803RPM | 804.2K/797.9Kh/s | A:264192 R:4608 HW:0 WU: 759.9/m I:20
 GPU 2:  78.0C 3703RPM | 776.8K/787.6Kh/s | A:239104 R:8704 HW:0 WU: 717.8/m I:20
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