So AMD graphic cards use seperate VRM for memory voltage.  The 5970 for example runs at 1.05V core and 1.10V memory stock.

All this talk of undervolting got me thinking.   2GB of RAM uses some wattage.  We are underclocking the memory 50% to 80% or more it likely can run stable at much lower voltage.  None of the tools I have seen allows the voltage to be adjusted DOWNWARD.

XFX Black Edition has a tool which allows memory voltage to be increased independently of core by up to 15% so modification is physically possible.  I guess XFX never though people would want to underclock the memory.

Any ideas?  Has anyone tried?

Yes I want to buy one. I may as well give it a try. If for some mysterious reason the PCB is different than the reference design then I may be out a few coins. I did a Google image search and the HD-587X-ZNFC is apparently a reference design VERSION 2.0. The version 1.0 reference cooler should work with some minor modifications (like cutting holes in the intake vents at the back to fit the PCIe power sockets (the v2.0 has them on the end of the card, version 1.0 has them at the top).

I'm located in Canada.

I'll PM you in max 1 hour...gotta get home.

I just recently purchased an XFX 5870 with the non-reference cooler, and I'm not liking the temp that it runs at when its placed in a system with another 5870. It runs at 73 C but a card with the reference cooler in a similar dual card mining rig runs at 63C tops - and that's overclocked to 900 MHz.

So, my question is this: Does anyone have a reference ATI 5870 cooler to sell me?

Edit: Hmm..I read somewhere that the non reference XFX HD-587X-ZNFC board is a bit shorter than the one with the reference cooler. Does anyone else have this card as well? Any solution to upgrade the cooling solution to one that exhausts out the back?

Hey scammer-bitch?

Have your lawyer call mine-Mr. Fuk U. Scammygerman Esq., at Dewey, Cheatum and Howe. Phone number in the US: 1-800-FUCK-OFF-AND-DIE.

Your lame ass scam failed, I hope the few pfennigs (or Eurocents, or whatever you Eurotrash scamming motherfuckers use) that was in that account was all of your worldly goods, and that now your pimp is going to beat you severely for losing the last few coins your criminal gang had to their names.

And from the way you write- a special message that I hope you mugu-boi can appreciate: wetin dey una come at heya? No find mugu, only great sorrow liek una two kobo whore sister an mutha workin sagbama exreswai lorry stop. Dis jobs no go, mugu liek u, all family get smash ded from u scam ways.

Which has nothing to do with nothing.

1) PV solar isn't that great for the environment.  It is made from a soup of highly toxic chemical and today 65% of it is made in ... China.  Yup those international bastions of clean manufacturing.

2) I would rather had 500 nuclear reactors than millions of acres of high cost PV panels.

3) Even if you are right it has absolutely nothing to do w/ the post you responded to which was about the ECONOMICS of PV SOLAR.

bulanula You got any improvement?
can able to mine with extender cables on BB marshal?

Nothing against cablesaurus, but the extenders they sell are the exact same one's you can get on ebay... for a fair bit cheaper.

I have all cablesaurus cables and still ran into issues as posted above. I have never bought from anyone else and also 4 have burned out on me in the pci slot but I believe that is related to trying to use two psu's or bad power fluctuations where the miners are. Even though I was told that two psu's should not be an issue, I would NEVER do that again. Even though Jimm64 has 30 GH/s of mostly 5970's, with extenders on MSI890FXA-GD70's with two psus and he says he is mostly rock solid. I copied that model and have been slaughtered so far.

EXTRA NOTE AND THIS DESERVES CAPS, CABLESAURUS WAS EXCELLENT AND EVEN SENT ME TWO NEW EXTENDERS AT NO COST AND WAS WILLING TO PROVIDE TECH CUPPORT TO HELP ME FIGURE OUT ANY ISSUES AT NO ADDITIONAL COST.

Cablesaurus is a GREAT BTC vendor. If you're going to bother with extenders, then go nowhere else in my opinion.

BTW my solid rig with extenders actually just started to lose hashing power again and looks like it at least needs a restart, so i'll hold off on my assessment of getting ANY rig to be solid with extenders.

This site really needs its own hardware wiki for individual hardware parts and known rig combos that WORK and what stats to expect. Would be a huge resource for all of us. The current online hardware wiki is crap and out of date.

I'd also like to see the site create a section for detailed guides. I think they could charge a monthly rate for access to such things, sort of a VIP membership, paid for in BTC of course

As RJK mentioned; those are the worst, because of the design. Its 2 slots and 2 sockets.
Without extender, so plugging a card straight in to the motherboard, you have a single non-soldered socket. With a regular extender cable you have 2. With your clumsy extender there are 4 per device!

check the slot switches in BB.
it has hardware switch to disable pcie slot 1,2,3,4 on top left.

It took more than 2 days for me to figure out that slot 3 & slot 7 NEED 16x extenders, while other slots work fine with 1x extenders.
I used extenders for all cards & no gpu is directly connected to mobo.
Try extenders for all.

When using only the two extended cards, is the rig stable? What about three cards? Have you tried using those cheap pcie1x-pcie16x powered extenders?
Are your pcie16x-pcie16x risers externally powered?
If they aren't, you may be drawing more juice with those four GPUs than the board is able to supply.
If the rig works fine with less cards but fails at four, make sure you use powered extenders.

Retuening to PSUs, do you have another PSU you could try?
The AX1200 is great but stuff happens. A few failed capacitors may result in elevated ripple levels.
The only problem is, you'd need a local electronics guy with an oscilloscope to be able to say for certain whether or not the PSU is to blame.
Much easier to just use another PSU.

A very decent PSU provided it's still in excellent condition. Good stuff... gold certified... the only thing it lacks is sugar frosting and a few specks of chocolate...  

What I was trying to say with my previous post is, if you're experiencing stability issues, make sure you have a decent PSU installed, that is isn't being overloaded, and - what should be obvious - that your machine is properly grounded.
A computer is no more than an electronic machine which needs to be grounded to work as expected.
A non-grounded PC (connected just with hot and neutral wires) will boot up and might function well enough for casual use but is still is in violation of the spec. Trying to push such a machine to hard work is asking for trouble. This simple fact of life seems to be often forgotten.
Pay close attention to the foundations guys, ok?

Its not just length, there is much more to it. Just the fact you have a connector is a huge issue and greatly limits clockspeeds and can introduce all kind of problems. There is a reason soldered GDDR (vram) is so much faster than socketed DDR ram (and a reason you can not socket GDDR).