I've just rebuilt my system after jumping to Skylake and I'm getting worse performance than I did with X58/980X. The GPUs are oc'd to the same as they were in the old rig but I'm getting HALF the score on Firestrike than I did on the old build. Same in Valley too. I've checked Afterburner and GPU load/temps etc appear normal. CPU isn't thermal throttling. Its sitting happily at 60c. I've overclocked to 4600MHz on the multiplier as normal - no change. Also tried overclocking with the bclk too - set that to 125 and lowered the multi for a 4625MHz overclock. Still poor frame rates. I even tried Win8.1 instead of Win10 - no change, same low scores. Any ideas before I RMA the board, cpu and RAM?
Is SLI enabled ? XMP enabled ? Your not going to see major gains I'd imagine either way. 980x at a decent clock was never CPU bound those gpus.
I'm getting 7500 +/- on Firestrike and Valley is finishing with 60-70fps on the Extreme HD preset. My 980x would push Firestrike to 16000 and 110fps on Valley. Yeah, XMP and SLI enabled. Like I said earlier, I can see both GPUs working in Afterburner so no idea what the issue is. Major gains, no - but I should be seeing gains, not a 50% drop in performance. Sent from my iPad using Tapatalk
Is this on a clean install of Windows as well? Your scores should be much higher, remember you'll have lost two cores and four threads, but your IPC gains should counteract that in the benchmarks. I get 12000 to 13000 with a single 980 with the 6700K at stock (tested on 14 different boards).
What's the bus interface showing as in GPU-Z when loading the cards? I'm getting 11,880 in Firestrike: http://www.3dmark.com/fs/7404025
I know this sounds daft, but try swapping the top card to the bottom, and the bottom to the top. I used to have a problem with dual cards that only emerged when a particular card was the first ( but that was CF not SLI).
I took a (long) trip up to Scan in Bolton today from London. 210 miles on a bank holiday & half term Friday.... Christ on a bike, it was an emotional drive... Anyway, they tested the kit on a bench and sure enough it came back faulty. TL;DR they refunded me everything and I repurchased the EVGA Z170 Cheesecake instead, got another sealed 6700k and RAM too. Can't build it until I get back to London on Monday though... Massive props to the guys at Scan. They were really helpful. I think they felt sorry for me driving all the way..
