Very cool, will look forward to hearing about your experiments. Quick update for me:

- I disabled "Cool and Quiet" under for my CPU in the bios, as suggested by a user on this thread: https://litecointalk.org/index.php?topic=14951.new;topicseen#new, but it didn't really change performance.
- I switched to a different mining pool, Shiftcoin for a day and my performance was somewhat dramatically better, at least in terms of hashrate. All of my cards enjoyed a 10+ Kh jump, was getting 715,720,740,710!

So it seems that the type of coin you are mining and/or pool you are participating in can also sway these results. When you guys are testing, do you mine just one coin, or?

Another 2.75Mh coming your way

lol, yes I can see now that we would essentially need to have a 1984 scenario play out in order to track something like this in an absolute fashion. Although if the promise of quantum computing pays off at least some of the things you mentioned would be possible. I didn't know that services like bitmixer existed- that pretty much nullifies bitcoin address tracking right there... I guess the thieves win in these instances.

Although- what if all bitcoin mixing services agreed to not accept coins from known illegal sources? Bear with me here... But what if an organization were founded that did nothing but track coins that were stolen in a way similar to what I suggested previously (watching the coins as they go from address to address ala "stolen gnome" style). Then, exchanges like bitmixer could cross check any incoming bitcoin mixing requests they get against the addresses provided by the organization? So there would be some sort of paper trail. Granted- ALL bitcoin exchanges would need to be doing this in order for it to be effective. But if they all did it it would actually benefit everyone because the general public would feel more confident using bitcoin as a currency and thus the overall value and use of bitcoin would increase.

Or would doing something like this invalidate some crucial part of what makes bitcoin relevant in the first place?

Hey guys,

I saw the news about Flexcoin being robbed. But the thought came to me, isn't it really impossible for the thieves to get away with this cleanly, in the same way a thief would if they stole cash from you? The block chain gives us a permanent record of where those stolen bitcoins are going, right? The thieves can take those coins and spread them out across a million other bitcoin addresses, but that doesn't change the fact that we can find out where it all went. If we used say, a Python script or similar to watch the load of bitcoins and trace exactly where they are going. So that still doesn't reveal the identity of the crooks, yes, but I'd argue that it eventually would. As soon as they exchange it somewhere, or buy something with it, they would have to give up their identity in some form to receive their good or service. Otherwise they simply have to sit on it, but that's as good as never spending your 401k. Unless they can find someone who is willing to take the coins in exchange for cash in an offline fashion I guess?

Maybe I'm missing something though. Does this line of thought have any merit?

I'd also like to know more about this- and about Trixx in general with these cards. I did one test last week where I lowered the voltage to 1150 and my computer locked up pretty quick. Has anyone here successfully lowered the voltage with their 11221-00-20G? Is trixx the best way to do this, or using the vddc argument in sgminer? Or within sgminer while it's running?

Quick generic update, my rig is still operating at about the same level ~700-710

Here's where I grabbed mine from: https://mega.co.nz/#!scgiiaaT!VvxjpA6KsURx2oMOm2t1GVvV9epWwC3nVncFPsUiZYw

thread: http://www.reddit.com/r/litecoinmining/comments/1va8g2/ann_sgminer_400_release/

Would you mind sharing all of your settings (copy / paste arguments) please? Also you mentioned about voltage, are you using Trixx, or something else? And you're using the same bios I uploaded?

thanks!

Just to clarify, your card is now performing at 780Kh? Settings please!

Did you use atiwinflash (in windows)? Or atiflash at a DOS command prompt (after booting in to dos only)? The .bin / .rom difference shouldn't be an issue as far as I know. Also this bios flashing thing is independent of any undervolting as far as I know.

Sorry I've been absent here for the last few days. Life always getting in the way! So I took a look in my sgminer folder, and the .BIN file that my miner created is: "scrypt130511Tahitiglg2tc8191w256l4.bin". So it looks like it's picking up the right kernel by itself. I'm not specifying anything for that in my arguments. Maybe you could try making a copy of your mining directory and delete all the .cl files in that one except scrypt130511.cl? Or have you found a workaround in the last few days?

Some people have PM'd me about the vbios which has apparently vanished from dropbox. Here it is:

https://drive.google.com/file/d/0B8TxUyvOU-ZtVnoxQ0xVWDltMVE/edit?usp=sharing

Included in the zip are 3 files.

• factory_bios.ROM - factory bios for the card when the UEFI switch is not on
• factory_uefi_bios.ROM - factory bios for the card when the UEFI switch IS on (indicated by blue LED on top of the card)
• Sapphire_E24900-O46_AGR.bin - the modified bios.

Use atiflash.exe at the command line (create a usb boot drive to go directly in to DOS, no windows). Personally, I recommend unplugging all of your GPUs except one and flashing the bios like that, one at a time and testing your windows boot up & mining for a few minutes. It's slow but you don't want to get in to a situation where none of your GPUs are working. Factory bios included in case you need to revert.

Some quick atiflash command:

• atiflash -i (information- this will list your GPU(s) and what bios they are using)
• atiflash -ai (advanced information- same as before, but with more info)
• atiflash -f -p # bios_file.bin (this flashes the bios. -f = force overwrite, -p # = specify which GPU by number, bios_file.bin = the bios file (can be .rom or .bin)

Good luck and don't forget to report back here.

FYI... required reading in this one. "hashrate isn't everything":
https://litecointalk.org/index.php?topic=2310.45

I did some math and I'm getting the following WU %'s for cards 0-3: 90%, 88%, 86%, 88%. That's 640, 624, 622 & 618 WU/s. Not to shabby, but also very interesting... because my GPU 0 is outperforming my GPU 2, even though GPU 2 has 17Kh/s more than GPU 0.

Also... this http://www.overclock.net/t/1461916/tutorial-ultimate-guide-to-tweaking-amd-cgminer-3-7-2-kalroth-edition-sgminer-instructions-included-aswell-get-the-most-hash-out-of-your-gpu

Time to tweak again.

WU/s = Work Utility / second. My understanding is that it's the actual usable data that your card is producing. You may be hashing at 740Kh/s but if your WU/s is 600, your card is doing 140Kh of nothing (except adding to the ambient temperature of your room and making your electric bill higher). But that's as much as I think I know (still a little fuzzy). Also I found this (explanation of cgminer interface), which is very helpful: https://doges.org/index.php?topic=5101.0

As far as the kernel goes, I simply renamed my existing kernel file "scrypt130511.cl" to "scrypt130511.cl.backup", and then copied the modified "scrypt130511.cl" file in to the same location as the backup. I didn't specify anything in my arguments, the miner just picks it up. Incidentally, how can you tell which .cl file the miner is using?

CGWatcher just gives you a nicer way to look at your stats, but I prefer to just look in the miner window since it's gives you immediate stats on what it's doing right that second. I primarily use CGWatcher because it can reboot the miner or even your computer if things crash. But it has a ton of other cool features like e-mail updates (which I just discovered yesterday, pretty cool). I notice that my hash rates jump up and down a lot in the first 15 or so minutes that the miner starts, so any time you make a change to your settings give it at least that long before determining if what you've changed helps or not. After it's been running for several hours the average rates should hardly change much at all. If it continues to jump around for a long time it may mean you're getting errors or lots of rejects (so I've heard).

That's as much as I know right now. Feel like I'll never be an expert at this though since there seem to be no end to the variables that can influence performance. Wish I were an engineer, alas I'm just a lay person trying to make a buck.

 

Quick update- I did some more tests this weekend.

• tried Powertune +20, this did pretty much nothing for me (but I'm not ruling it out, it may be configuration dependent. Will experiment with this again later)
• tried --thread-concurrency 11200: Not really any improvement. I keep trying this because I read in a tutorial a few weeks ago that to find your optimal TC number, you should start your miner with no TC argument and then see what it defaults to (found in the file name of the BIN file that's generated). When I do this it always uses 22400. So- since I'm using -g 2 (two threads rather than one), it *should* be 11200 for me. But, apparently it's still not. (may try again later... or maybe tri 11199??)
• tried --thread-concurrency 8191 again: BAM! Hashrates jumped up. Now running a pretty stable 705,710,720,700 avg. hash rates across GPU's 0,1,2,3. Has been running stable for 24+ hrs now.
• 8191 required that I could no longer use the pre-generated 8192 BIN file that I mentioned in previous posts. Seems to have made little or no difference, which makes me wonder if it was really helping initially or not.

http://i.imgur.com/govhIrK.jpg?1

Current arguments are:

Up next, going to experiment with...

• Lowering the voltage via TRIXX to see if I'm dealing with an overheating and therefore throttling VRM issue.
• Ways to increase my WU/s and see if I'm actually getting my money's worth out of my hashrate (if hashrate is doing awesome but WU/s is low, what's the point??)
• Ways to reduce rejected shares (what's the point of having an awesome hashrate if the pool is rejecting your work...??)

Comments always welcome. Thanks for taking the journey with me!

Thanks CryptoMer, this will be my next line of inquiry with my on-going tests.

Quick update, I noticed today that my high performing card (GPU 2) has SK-Hynix based RAM, the other three lower performers use Elpida. Not sure what this means for me going forward, but it's a clue. Starting to feel like a detective over here Input welcomed!

Hey everyone, I wanted to share some good results. Thanks to NameTaken I've been able to bump things up:

http://i.imgur.com/XnSNkDF.jpg?1

Just to reiterate, what I did exactly was first switch over to the optimized .BIN files with SGMiner (since I'm running 64bit windows I had to change the last digit in the file name from an "8" to a "4" for sgminer to use the bin). Then I loaded in the optimized .CL file (backed up old .cl file first). I let that run for a few days because I got busy, noticed about a 5-10Kh bump overall, up to an average 675-680Kh per card. Then as of last night I went ahead and flashed my cards with the bios that NameTaken pointed me to, and that finally allowed me to break the 700 barrier. The screenshot above is from this morning after the rig had been running for about 7 hours. (links for all files below)

It's interesting but my GPU 2 card has now become the best performer whereas before it was GPU 0. I'm getting a very reliable 720Kh out of it. Meanwhile GPU 3 is doing the worst at 685ish. I didn't have much time because I was getting really tired, but I did mess around a little with the gpu-engine settings and right now I have it set as "--gpu-engine 1065,1075,1080,1030". Yup, doesn't look like a good config does it? But that seems to be my sweet spot (so far). GPU 2 loves the extra engine speed, it jumps 10Kh when I move from 1065 to 1080. And it's the reverse for GPU 3, which either does nothing or goes down when I go over 1030. But I do need to play around with it a bit more, maybe next week.

I've been trying to find the optimal GPU temperature also. I notice that at 75C the cards definitely throttle back a bit. I have it set to 68C as a target right now but I may be going to far and wasting energy on fans (any thoughts?)

I'd still like to see if I can inch things up a bit faster than this. But I am very pleased with the results (and thanks to everyone who helped!). Later on I'm going to try and trouble shoot GPU 3 and also see if GPU 0 & 1 can't do more. Then I'd like to do some voltage experiments to decrease the power. I also have an average rejected share rate at about 3-4% which I think I could lower too (although I have no clue where to start).

• BIN file thread: http://www.reddit.com/r/dogemining/comments/1uj4uk/optimized_scrypt_kernel_for_hd7970_r9_280x/
• BIN file direct link: https://drive.google.com/file/d/0B_EJYw4JvsnvazdqQW5DWTVzcFU/edit?usp=sharing
• .CL file (it's inside the zip in a folder called "files"): http://fs1.d-h.st/download/00099/G2D/ati_winflash_2.6.7.7z
• BIOS file direct link: https://www.dropbox.com/s/jfmog1a8inexrvy/Sapphire_E24900-O46_AGR.zip (don't use atiwinflash, use atiflash at DOS prompt (need to make usb DOS boot drive))
• ATIFLASH 3.99 (I was advised to use this version of the app, not the latest one): http://www.techpowerup.com/downloads/2166/atiflash-3-99/

Here is my current config that results in the screenshot above:

I left out Powertune for now although I'm going to experiment and see if it changes anything. Also might experiment again with thread concurrency in the 11200 range. Will post back with results. Oh, and one last thing- I noticed that CGWatcher does some damage to my hashrate because it is always pinging the GPU's for information. I was able to solve this by changing the monitor from checking in every 10 seconds to every 180 seconds (every 3 minutes). This seems like a good fit because I still have the benefits of CGWatcher being able to reboot the miner if something goes wrong.

Comments / critique / whatever welcome.

I applied the modified .BIN and .CL files last night, and my hash rate improved marginally by about 5-10Kh. Haven't had a chance yet to flash the bios, but will try soon.

Interestingly not all of my cards are performing at the same level, GPU0 consistently beats out the rest at an avg 690 now. GPU1 and 2 are around 675 and GPU3 doing the worst at 665.

Awesome, I'll try this tonight and report back here. Just to be clear, you used the bios that The_Stilt posted in reply #102, correct? This one: https://www.dropbox.com/s/jfmog1a8inexrvy/Sapphire_E24900-O46_AGR.zip

Asking because I flashed one of my gpus with some bios from his thread about a week ago and it bricked it until I used the physical bios switch on top of the card. Trying to be more cautious.

thanks!

Your performance rates sound fantastic. Would you mind sharing those files (bios, .c and .bin files) via dropbox or similar? Also what type of memory do your cards have?