Yeah, sorry... I've tried selling things outside the US, but got screwed on unexpectedly high shipping costs.  Ends up not being worthwhile to sell to Puerto Rico even.  eBay considers them to be within the US just because they're a US territory.

And?

The 2 Radeon HD 6990's I'm selling on eBay have ONLY 4 HOURS REMAINING!!  These cards are only 3.5 months old.  They are awesome at hashing, exceeding my hashrate expectations at about 740 MH/s each, not to mention that games look deliciously smooth on these bad boys.  Crysis 2 runs like butter on max settings as does Deus Ex: Human Revolution.

Check them out!

http://www.ebay.com/itm/170701175886
and
http://www.ebay.com/itm/170701176166

Happy bidding!!

Bump.  If this is not allowed, will someone please let me know?  I won't do it again if that's the case.  Thanks.

Eeesh... thanks for the warning.  I did see a lot of variance in the final sale prices when I looked through the auctions that had already ended.  Some recent ones went for $700, but other were closer to $600.  Fingers crossed.

I'm selling two Sapphire Radeon HD 6990's.  These cards are amazing at mining and I wish I didn't have to give them up.  I got consistent hash rates of 744 MH/s each, using CGMiner.  Below, are the eBay links.  The bidding started at $0.99 each and there is no reserve.  Six and a half days left (as of this writing).  Check them out.

http://www.ebay.com/itm/170701175886

http://www.ebay.com/itm/170701176166

If you're interested I can tell you the CGMiner parameters and which drivers I used, etc. to give the best stability and hashrate conditions.  I kept them air-conditioned for cooling.

Please feel free to ask me anything you want to know about them.
Merry mining! 

Thank you for the articles on scalability.  I'll take a look.

I wish I could be this optimistic.  In action, I am hopeful; I'm still gung ho about mining, partially because I've invested about $3000 in my rig, not to mention all the electricity I've spent on mining.

However, I am not quite so optimistic about the real future of the Bitcoin's adoption as a currency for everyday use in all the scenarios where today we use fiat currencies.  The major reason for my doubt is with the infrastructure requirements.  Even now, in what we consider Bitcoin's infancy, joining the P2P network requires the download of a rather long block chain.  And, every client that wants to make transactions has to continue to constantly download all the data about every transaction that occurs.  That may not take much bandwidth today, where most of the transactions are just a few thousand trades per day.  Expand that to a commercial payment system where Billions of people around the world are using Bitcoins to buy everything from a house to a pack of gum at the gas station, and you have a serious bandwidth problem.  When obviously you'll want your smartphone to be holding your everyday wallet, no device short of a multi-terabyte workstation hooked up to an OC-3 will be able to keep up with the bandwidth and burgeoning size of that transaction list.  Even at today's rate, I doubt anyone's smartphone battery could last the day running a Bitcoin client.

Unless some revolutionary changes are made to the entire system, I'm afraid this problem will quickly kill the Bitcoin as a real means of value exchange.

I would love to hear about a solution to this problem because I sincerely want to see the Bitcoin succeed.

A suggestion, if I may:  Make the automatic payment feature payout the whole balance.

Currently, if I hit my threshold of say 3 BTC around noon, I don't get paid until 2300 (which is fine; I don't care about the delay).  But, at that time I only get paid 3 BTC.  This leaves behind a balance of whatever I made between noon and 2300, which complicates determining my hourly or 24-hour earnings.

Shouldn't matter; ABCPool pays for stales. 

I noticed my invalid rate was pretty high to begin with (2-3%).  But, I've had very few invalid shares lately, so my lifetime invalid rate has dropped to 0.78% over the past couple days.

However, I have also noticed that ABCPool stats generally report my hashrate to be between 1950 and 2150 MH/s, while my mining client consistently reports 2200 MH/s.  One would think that if the Current Hashrate statistic on the site is a 10 or 15 min. average, I would be seeing my hashrate over 2200 sometimes and under other times.  It's difficult to tell if this problem is affecting my income since I can't see any 24 hour stats to compare to my previous pools.  I guess I'll have to start manually logging my balance at certain times of day. 

Could you please add ABCPool.co?  Thanks!

Thank you!  I love your avatar, btw.  Patrick Bateman is my hero. 

Please let me know when I can register.  I would love to join this pool and have it as my primary.  I promise to donate!

Lol...  I know, right!  I kinda want one, but it would just tell me the same thing my electric bill tells me every month:  "Your wife is going to kill you."

746287 what?  Units, please!

Also, please don't waste your time CPU mining.  You're spending more on electricity than you're making.

I agree.  Do away with CPU mining altogether in CGMiner.  You'd be doing people a favor by not letting them waste electricity on an unprofitable venture.

Try CGMiner... https://bitcointalk.org/index.php?topic=28402.0  It automatically restarts dead threads and supports multiple failover mode (switches pools when your main one gets DDoSed).  I'm a big fan.  It has given me better performance and up-time than any other miner I've tried thus far.

And on the issue of letting the cards rest, I'm with MaGNeT on that one.  Run 'em 24/7/365 if you can.  Ideally, you would never have to touch your mining rig once it gets started.

What I've found is that it appears to use 100% CPU, but that processing time is not actually tied up.  I can mine on two of my 6990s and play a very demanding game on the other one (which I assume is also using shit-tons of CPU power, and not experience any slowness from either application.

So, I think the 100% CPU problem shouldn't really be a consideration when choosing drivers... unless your experience had been different.

It's an 80 Plus Gold rated supply (Enermax MaxRevo), so it should be pretty efficient.  I wish I could tell you how much I'm really pulling, but I haven't bought a Kill-A-Watt yet. 

I have a 1350W PSU running 3x6990 just fine.  I don't have anything over- or under-clocked, and my hash rates are great (~2200 MH/s).  The system also includes an AMD Phenom 4C CPU at 2.66 GHz, 8 GB RAM, and other normal PC components to make it a usable system for gaming and such -- in case this whole bitcoin thing doesn't work out.