I have gone from 900 to 1100 on my gpu clock. It just slowly increases each time i move it up. No sweet spot no big jump at any spot. Really weird if you ask me.
I am now at 1100/1575/1.102v and getting 596khash/s
Update for ya, I found a ASUS 7970 bios modded by The Stilt that can boost my card up to around 711KHs. I'm still testing the stability will keep u informed very soon, still finding the highest hash rate so far.
Also I changed my minier to sgminer 4.1.0 as that's the newest miner available, Driver still 13.1. script:
setx GPU_MAX_ALLOC_PERCENT 100
"sgminer.exe" -u icrazynoob.1 -p x -o stratum+tcp://global.wemineltc.com:3335 -w 256 -I 13 -g 2 --thread-concurrency 8192 --temp-cutoff 85
EDIT: also when your increasing your core clock and hash rate goes up that's a good sign, keep going up til u hit the point where it DROPS. and that last clock where it didn't drop is the sweet spot.
EDIT2: After a few hours of tuning I have gotten my card to run at
750KHs @ 1070/1500/-20% Power tune/80% Fan @ 73C. Gotta say I'm pretty satisfied. The card seems to be able to handle even higher speed but I'm playing it safe as 1070 is already fairly high clock.
For this BIOS MEM CLK stays @ 1500 as specified by The Stilt due to the BIOS contains modified CL timing. Just raise your clock from 1000 with 10 increment til it either drops or if temp is reaching GPU ~80C /VRM ~90C. My still goes up even after 1070 But like I said, I want choose this place to stop at around 750KHs for safety.
BIOS:
https://www.dropbox.com/s/cgaaubvsnw9uh0w/7970MOD.binHP USB Disk Storage Format Tool:
http://download.cnet.com/HP-USB-Disk-Storage-Format-Tool/3000-2094_4-10974082.htmlWIN98 Boot:
http://www.bay-wolf.com/utility/usbkey/win98boot.zipATIFLASH 4.17:
http://www.techpowerup.com/downloads/2306/atiflash-4-17/If you don't know how to flash heres the post where I learned it:
http://forums.guru3d.com/showthread.php?p=4503953PS: My card is
Powercolor AX7970 3GBD5-M2DHV2, with
SK Hynix H5GQ2H24MFR VRAM Chips. Have the reference AMD red/black Turbine cooler.
PSS: when you are putting the atiflash.exe in the usb its easier to name it shorter as DOS tend to shorten it as ATIFLA~1.exe which is a PITA to type.
PSSS: back up your current BIOS from GPU-Z and name it 7970Ori.rom so you can flash back in case of failure. Flash the BIOS 1 on the card. the switch is near the CF bridge.
Hope this helped you! I'm still waiting to sell my gaming machine for money so I can get a mobo that can run all 3 of my cards together haha. Right now only one card its sitting in this old HP machine with AMD 4600+, 4GB DDR2 533 RAM and an Antec 450W PSU
and it still hashes 750KHs without a sweat xD