I posed this question to #bitcoin, and they weren't very responsive, so here's a chatlog of my thoughts that I'd like to get some feedback on.

Code:

[16:35:02] <NLA> maybe I'm just not seeing it
[16:35:10] <NLA> but has anyone done some calculations
[16:35:20] <NLA> based on the BFL ASIC waiting thread
[16:35:30] <NLA> as to what the project difficulty will jump to
[16:35:39] <NLA> in October/November/December
[16:36:04] <NLA> and how that will affect how much that will affect the profitability of the different BFL ASIC
[16:36:49] <NLA> ie. at the current moment, the BFG of the bunch, the SC Minirig, estimated at 1500GH/s by BFL, would currently earn $180,000/month at current rates

[16:37:02] <NLA> obviously the difficulty is going to spike up when BFL starts delivering preorders
[16:37:21] <NLA> and likely small miners are going to be forced out due to the difficulty spike
[16:37:31] <NLA> but it seems like a lot of threads are ending there and focusing on the little guy

[16:38:06] <NLA> what I'm interested in is what happens to the big guys? does $180,000/month today become $30,000/month almost overnight? or $15,000? or $1,000?

[16:41:22] <NLA> Take for instance http://blockchain.info/charts/hash-rate and https://bitcointalk.org/index.php?topic=89685.0
[16:41:42] <NLA> if the current overall network hashing rate is estimated at 25TH/s
[16:41:57] <NLA> and based on the data from the wait list
[16:42:11] <NLA> which will likely not cover all the pre-orders made to BFL
[16:42:33] <NLA> of a total increase of 48.339TH/s when everyone receives their units and flips the switch on
[16:43:22] <NLA> thats almost a 3x increase in total hashing rate, and therefore a linear increase of 3x difficulty to accomodate the increased hashing rate

[16:43:50] <NLA> Consulting a simple profit calculator http://www.alloscomp.com/bitcoin/calculator
[16:44:31] <NLA> and multiplying the difficulty by 3x and plugging in 1500GH/s
[16:44:48] <NLA> results in an expected return of $59,924.51/month
[16:45:17] <NLA> which is significantly down from $180,000 but is still reasonable
[16:45:44] <NLA> but if everyone quits mining because the difficulty is so high
[16:45:56] <NLA> and lets pretend the exchange rate of bitcoin falls to $5/coin
[16:46:22] <NLA> that results in an expected return of $25,024.91/month

[16:47:40] <NLA> and I could what-if further along all day and make wild assumptions, but has anyone actually thought about the implications for the big guy, the guy that dropped $30K on a Minirig SC?

Thoughts, anyone? Am I overlooking some possibilities here? Is it possible for Minirig SC owners to net $180,000 for a month or two before, say, the block worth is cut in half, or the network collapses, or is it possible that almost upon arrival that Minirig SC owners will net $10,000 first month, $8,000 next, etc., and never earn back their initial investment?

Topic says it all really. Right now I have two rigs running with 7x 7970's, and I've been mining with EclipseMC as DGM, but I'm wondering if maybe there's a better pool out there that I could apply my 5GH/s to? I enjoy EclipseMC's perks, such as

• Google Voice-compatible SMS messaging (!)
• PaypalDwolla instant cash-out option
• Fancy added-security authentication options
• Fairly high pool mining speed, for fairly quick block solving (and thus fairly quick payout via DGM)

Any opinions?

Also, at the moment, I'm mining as DGM, but I'm wondering if with 5GH/s I should switch over to PPS or some other variant. My (likely wrong) understanding of DGM is that you're paid a set amount based on your hash rate, not so much based on the number of shares you contribute in a round.. but wouldn't that mean then that I would want to switch to as fast a pool offering DGM as possible? And I haven't done too much investigating into whether I would make more as PPS than DGM, but can anyone shed some expert opinion into this? I'm just a hardware guy at heart, trying to earn some moneys. Halp?

Currently testing my 7970's in Windows before I flash the BIOS to the settings I want (voltage, clocks, for maximum performance) and switch over to mining in Ubuntu, and I'm testing with AMD's 2.7 APP SDK. When I'm mining with just one or two cards, I hit 99% GPU usage and I get all the performance out my 7970's; when I'm mining with five cards, GPU usage wildly fluctuates between 70-86% and I net substantially lower hashrates. What gives? Less GPU utilization equates to lower hash rates! I'm suspecting that either the SDK or mining in Windows itself is to blame.

Specs:
5x 7970's: 2 Diamonds, 3 Sapphires
Windows 7 Ultimate x64
AMD 11.12 Drivers + AMD APP SDK 2.7
cgminer: process priority high, CPU usage between 6-15%, poclbm kernel, 2 threads, intensity 10, powertune 20, mining with EclipseMC

• Any suggestions?
• Any evidence to the contrary that SDK 2.7 works just fine? Is it just me having the issue?
• Do the Linux and Windows SDK's have the same performance, ie. if SDK 2.7 is netting 70-86% GPU usage in Windows, it will be the same in Linux?
• What is the best SDK to use with 7970's in Linux? In Windows?

I've built a nice dual-GPU rig with 7x 7970's in an open-air rig I made from spare parts. 5 of them are connected to the motherboard via 1x to 16x riser cables, and 2 are connected via 16x to 16x riser cables. The 5 connected via 1x to 16x work just fine and can be mined, but the 2 connected via 16x to 16x have some sort of issue and are not available for mining. In Windows Device Manager, the 2 cards list "Code 43" as the error, and they are being prevented from starting. I've done a clean driver re-install with atiman, and I'm using the 11.12 drivers (which support up to 8 GPU's), and I have no idea what has gone wrong. I wonder if I need powered 16x to 16x risers from cablesaurus (or somewhere cheaper, preferably).

Anyone have a similar issue?

• 7x 7970's: 2 Diamond's, 5 Sapphire's
• Dual GPU's: 1x 1600W (connected to 5 GPUs), 1x 750W (connected to 2 GPUs)
• Motherboard: GIGABYTE GA-970A-D3
• Windows 7 Ultimate 64-bit
• AMD 11.12 Drivers, for >5 GPU support
• Clean driver re-install with ATIMan completed, same issue
• 1x to 16x cards recognized and functional
• 16x to 16x cards non-functional, code 43 in Device Manager

Halp?

PS Please no one buy the dual fan Sapphire cards, they look impressive but the fans don't spin fast enough to cool worth a damn (~3300RPM cap), and they're not designed properly to move heat out the back of the card (they just gently direct heat everywhere).

EDIT: Just connected one of the 16x to 16x cards to another slot via 1x to 16x cable, works just fine. The issue is definitely either the cable or the 16x slot. Halp?

So I did some searching this afternoon on Google and around the forums, and almost all chatter about pool hopping seems to have died sometime around December and January. Few hopping-related threads have popped up within the past 4-5 months. I see there is still some activity in certain pool hopping clients (bitHopper) which seem to have continued development, and no activity in other once-popular hoppers (CherryPicking).

This makes me wonder, is pool hopping dead? Is there no extra profit to be made from hopping anymore? Are all pools immune to hopping nowadays? Whats going on? What happened to all the interest in hopping?

[64GB, WiFi + 3G]

Hello everyone! I'm looking to sell my original iPad1 in light of my iPad2 purchase.



Photo Collection: http://imgur.com/a/DcGSd#kfZZH

It's a 64GB, WiFi + 3G model, and it includes the Dodocase I bought for it way back when, as well as another case, all the original contents of the iPad1 box + box, and the Apple wireless bluetooth keyboard + box. The iPad is in fantastic condition, and shows extremely minimal signs of wear -- you actually have to sit down and really look for signs of wear to find them. They're virtually unnoticeable on a day-to-day basis. I've always taken good care of the iPad, I'm not a smoker, I haven't spilled anything on it, I've always kept it clean, and the screen is in **perfect** condition. The Dodocase is in used condition, it shows some signs of use, but it feels very natural in the hand, very smooth.. a good kind of "worn", like holding an old book, which is what the Dodocase designers were going for in the first place. The keyboard is in perfect condition, just never had a chance to use it as much as I would have liked.

The iPad works perfectly, no screen cracks or issues of any kind, the bluetooth keyboard works perfectly, and price of shipping for everything is included in the price. I have no qualms with jailbreaking, but keep in mind that the iPad will arrive completely wiped of software and will be essentially factory fresh.

I'd like to try to sell here instead of eBay only because eBay = Paypal, and they charge ~$25 each for listing the auction/receiving payment, which I think is absurd. Having said that though, my price is going by the typical eBay selling prices for these (with all the accessories). Check me out on eBay:

http://myworld.ebay.com/starmenet

I'm a 100% seller on eBay, so feel free to send me a message to check that it's really me. Everyone I've ever dealt with on eBay has always come away happy.

Price: 122BTC

I think this is very fair considering all the accessories and the included shipping. For an additional 6BTC, I will ship priority internationally to anywhere in the world. Domestic or international, the package will be fully insured.

Thanks for reading! Let me know if you have any questions.

I think it's interesting that there is a thread for posting pictures of mining rigs, but no thread for posting (read: bragging) about highest core clocks managed on cards, and the configuration that went into it, etc. What works for one person with one card might help another person with the same card, etc. I'll start.



GFX Card: Sapphire 6970
Core: 1030MHz
Mem: 150MHz
VCore: 1225mV
Fan Speed: 100%
Consistent Mining Temp: 69.5C
Stable for at least: 24 hours

This card is an absolute champ, has always run cooler than the others no matter what slot I put it in. (I have one of these, http://www.drillspot.com/pimages/213/21333_300.jpg, directly blowing into the case.) Looking to up its VCore a bit further so I can increase the core clock a bit more and get the temperature in line with the others. My philosophy: push it as hard as possible until the temps are about the same for all cards, and stay below 80C if possible!

If you spent a long time searching through Google for a solution and my troubles helped you, consider tossing some BTC's my way.. 1HayA42ajEr19iEaeJbLLkPyKYMve2U4T2

So yesterday I decided it'd be a good idea to reduce the amount of electricity I pull from the wall when mining by flashing the BIOS of my 6990 (master and slave BIOS) such that the memory clocks are always at 300MHz. I flashed through Windows with the ATI BIOS flash utility (winflash? atiwinflash?) and the utility reported that the flashing was successful. Upon rebooting into Linux, I ended up at a blank screen and the OS was unresponsive.

Keep in mind that NOTHING had changed in the mean time with Ubuntu -- it was working fine, I switched to Windows and flashed the BIOS, rebooted to Ubuntu, frozen at black screen. So after backing up all my files and such, I completely re-installed Ubuntu, re-installed all the necessary files for bitcoin mining, and updated the rig, and then rebooted. BLANK SCREEN. So just now, I toggled the BIOS switch back to the backup BIOS, and voila I'm back into Ubuntu just fine.

Anyone else have this issue with BIOS flashing? Has anyone managed to flash the BIOS of a 6990 and have it work just fine? Is there something special I need to do to flash properly? Literally all I did with RBE was adjust the memory clocks to be 300MHz across the board on the master and slave BIOS, and I ran into problems.

Halp plox.

EDIT: My problems are similar to https://bitcointalk.org/index.php?topic=8447.0, but I have my master/slave BIOS backed up. My problem has to do with Ubuntu not wanting to boot with my modified BIOS on the 6990.
EDIT2: Took me a while, but I actually found someone that has been messing around with BIOS flashing the 6990.. http://www.overclock.net/13034600-post601.html.. he only covers volt modding through RBE and doesn't mention underclocking the mem, and he mentions to only adjust voltage on the VID4 GPU register entry.. Hm..
EDIT3: Just reflashed to a slightly different modified master/slave BIOS (underclocked mem, voltage bumped to 1200mV instead of 1175mV) and same problem, Fgsfds. Has anyone managed to BIOS flash their 6990 properly?

Still open to suggestions/thoughts/advice!

Evening all, this will be my first post on the bitcointalk forums.

I've been around for a while, reading through guides and keeping track of everything enough to build myself a rig with the following specs (from Newegg):

• 1 x Antec One Hundred Black ATX Mid Tower Computer Case
• 1 x SAPPHIRE PURE Black P67 LGA 1155 Intel P67 SATA 6Gb/s USB 3.0 ATX Intel Motherboard
• 1 x Intel Core i3-2105 Sandy Bridge 3.1GHz LGA 1155 65W Dual-Core Desktop Processor BX80623I32105
• 1 x Crucial Ballistix Tracer 2GB (2 x 1GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory w/ Green LEDs Model BL2KIT12864TG1608
• 1 x MSI R6990-4PD4GD5 Radeon HD 6990 4GB 256-bit GDDR5 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Video Card with Eyefinity
• 3 x SAPPHIRE 100311SR Radeon HD 6970 2GB 256-bit GDDR5 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Video Card with Eyefinity
• 1 x SILVERSTONE ST1500 1500W ATX 12V 2.3 & EPS 12V SLI Ready 80 PLUS SILVER Certified Active PFC Power Supply
• 4 x COOLER MASTER SickleFlow 120 R4-L2R-20AR-R1 120mm Silent operation Red LED case fan

I kinda went all-out on building this one, ended up costing ~2700USD. I also built this back when the price of bitcoins were much higher.. I had expectations of making it big. Those were the days, eh?~

Anyway, so I've finally gotten all of this set up with Ubuntu 11.04, such that I plug the system into the wall (directly), power it up, after 5 seconds or so it boots into Ubuntu from an internal SSD, its set up to automatically connect to the wireless network in my house, and it runs VNC and Hamachi on boot for me to remotely access it. I plan to eventually have it automatically overclock and start mining on boot after 20 or so seconds.

IT ALL SEEMS TO WORK FINE, except for when it comes time to actually mine. 2 of the 6970's I've left with the stock BIOS voltages, one I have overvolted in BIOS to 1225mV, up from 1175mV stock, and I've left the 6990's alone BIOS wise. The BIOS switches on all the cards are set to the 'enthusiast' warranty-killing mode. I set all the core clocks of the cards to 900MHz (seems like a safe overclock, up from 880MHz stock), and that one special 6970 -- which is special because I've stress tested it enough to know that it can run @ 1000MHz for at least 6 hours straight under full load without hitting 83C -- I set to 990, just to be safe.

Mining runs for a few minutes with phoenix, and after a few minutes the system crashes. Flat-out sudden shutdown. Fans stop spinning, the works. I look through the case, and the LED's that light up to indicate that the PC is on are still on. I hold the power button for 7 seconds to shut them (and the system?) off. I try to power it back up -- nothing. Just like before, the power-on LED's are active, but I'm assuming the PSU isn't providing the juice since its status light is red.

So here's the thing. I'm wondering if I have a defective PSU. 1500W should be enough to power 3x 6970's and 1x 6990, right? I've underclocked the memory on all the cards to 180MHz (the lowest I can go before I notice a performance hit in MH/s), and the CPU is obviously a low-tier model which is not overclocked, and I haven't overclocked the system RAM, so I'm not sure where to point the finger here. This 1500W supply is supposed to be REALLY GOOD. It has a great rating on Newegg, it's very efficient, and its 1500W. I can't imagine that I'm exceeding the wattage requirements with these cards mining. Or am I?

I really wanted to post this in the Hardware forums, but since I'm restricted, here I am. Halp.