I suggest you use the 1000w in the mining rig, and underclock the memory on both cards to save on power usage.

My 4870 saves 30 watt by underclocking from 900 to 190. You could see similar savings on those cards, giving more headroom for overclocking core, while still being within 1000W.

I suggest you use MSI Afterburner to do the underclocking if it's on Windows.
Install it and go to the installation directory. Open the MSIAfterburner.cfg and scroll down until you find "[ATIADLHAL]". Replace that section with the following:

[ATIADLHAL]
EnableUnofficialOverclocking   = 1
UnofficialOverclockingEULA   = I confirm that I am aware of unofficial overclocking limitations and fully understand that MSI will not provide me any support on it
UnofficialOverclockingMode   = 2
AccessibilityCheckingPeriod   = 0

When you underclock then, you need to close MSI Afterburner and reopen it after turning the memory clock to it's lowest. Repeat until you get down to the clock you want.

If you can do it, and the cards remains stable, you can also undervolt it to save on power and heat.

That's the last phrase of someone gunning for the Darwin award.

Seriously, playing with electricity that contains enough amps to kill you outright is NOT something that is recommended, unless that is your job and you've got education to back it up.

On my 4870, I have seen the best result using poclbm using -w 256 -f 60 and SDK 2.1.
I used MSI Afterburner to downclock memory to 190, which increased my hashrate by a few MH/s and lowered temperature and power usage.
Overclocking to core to 830 then yielded the current 100.4 MH/s I currently see.

Bumping -f 60 down to -f 10 got me 104.6 MH/s, but since I use the computer also, that gives too much interface lag.

To be able to underclock memory to 190 with MSI Afterburner, you need to unlock the safeties on it.

Open the MSIAfterburner.cfg and scroll down until you find "[ATIADLHAL]". Replace that section with the following:

[ATIADLHAL]
EnableUnofficialOverclocking   = 1
UnofficialOverclockingEULA   = I confirm that I am aware of unofficial overclocking limitations and fully understand that MSI will not provide me any support on it
UnofficialOverclockingMode   = 2
AccessibilityCheckingPeriod   = 0

When you underclock then, you need to close MSI Afterburner and reopen it after turning the memory clock to it's lowest. Repeat until you get down to the clock you want.

The network regulates difficulty to produce about 6 blocks each hour. So those will last roughly 12 days.

You said it yourself, it's not precise enough. Only having the total shares does not say much about the actual income. As the difficulty changes, so does the value per share.
It is hard to extract how many of the shares were mined during what difficulty, making it hard to put a total estimate on workers that span many difficulty changes.

So a timeline over shares/dificulty at least would be nice.

I propose wind/solar powered mining farms, which would make mining free.

A question Tycho, would it be possible to add total average income for a worker?
So if a worker is active 8 hours one day, and 6 hours the next, it will show the total average income for those 14 active hours.

All numbers are measure at the wall socket, and remember that I've underclocked the memory, which removed 30w measured at the wall.
Also, I've got a Core i5, and it underclocks itself when not being used. In addition, I have SSDs as main drives, and only one HDD for storage. So the main energy eater is the card.

And I'm sitting at the computer most of the hours it's on, which is roughly 17-18 hours a day, which I've now complemented with mining during that time. I can't sleep with on anyway as it makes too much noise.
And since it's not on 24/7, I don't run any kind of services on it. Even if I did, they'd be using CPU and not GPU.
When I browse the web, which is what I do the most, the hashrate lowers to 84-87 MH/s when jumping pages or reloading.

The way I see it is, is that as long as I'm doing other stuff on the computer, and I get more bitcoins worth than the electricity costs, I'm doing something useful with my spare processing power.

I do have two 5870 coming that I'm going to mine with. But I didn't buy them just for that though, as I want to upgrade for BF3 etc. Mining only accelerated the purchase.
That I can possible get my money back by mining is icing on the cake that is running the latest games.

I've just reflected the code, and it's completely safe.
The only thing to comment on would be how the code looks. Though since .NET Reflector is pretty good at decompiling good code in to hard to read code, I'd have to leave that uncommented until I can see the actual source code.

Do you mean CCC? It has nothing to do with Bitcoin.
It's "Catalyst Control Center", the full driver software suite for Radeon graphics cards, which happens to include OpenCL which is needed to run GPU miners.

You can do pooled mining with GUIminer, which you already downloaded and tried.

*Moved to new post*

Since you had problems detecting it in GUIminer, I suggest you download the latest full CCC from ati.com. Here is 32 bit version, and here is 64bit version.
If you don't know what version you have, go to start menu, right click on computer and select properties. Under the system header, which has the Windows Experience Index, there should be a label called "System Type", which tells if it's 32 bit or 64 bit.
Install the correct one and restart your computer. OpenCL should be installed now if you didn't have it before.

If the computer is a dedicated miner, you can run a worker on GUIminer with the extra flags -w 256 -f 10. Bit if you, as I do, use it normally, run it using -w 256 -f 70, as that doesn't slow the GUI down nearly as much.

For me it's quite profitable.
The energy price here is $0.233 per kw/h. Seeing as I use my computer normally during mining, I'm only interested in the difference between idle and load, which is 80w on stock.
Overclokcing core and underclocking memory yields a 5w increase in difference between idle and load, but a 30w decrease in total usage. This gives me an effective cost of 55w for mining.
At $0.233 per kw/h that equates to $0.308 each day. 1BTC is currently at $16.33 on mtgox, and at 94.5 I would get roughly .02 BTC a day on deepbits PPS model.
So each day I get about $3.27 worth of bitcoins.
Now if it would have been a dedicated mining rig, the total power draw is 210w, giving a daily energy cost of $1.17, which is still profitable at current prices.

Writing it up, give me a sec.

That is also wrong. I have a 4870 as the OP, and standard I got ~82 MH/s with poclbm -w 256 -f 60.
Since I'm also using the computer normally while mining, the only real cost is that of idle vs full load, which is 80w at stock speeds.
By overclocking core and underclocking memory to 830/190 I get to 94.5 MH/s, giving an 85w effective draw during mining, but overall 30w lower due to memory underclock.

So it is most definitely profitable.

I'm running poclbm, and it's doing LP fine.

Thought I'd post my results on underclocking memory.

I run an ASUS 4870 DK using poclbm -w 256 -f 60.
Trying the clocking around I got to ~92.5 MH/s @ 830 core and 900-300 memory using MSI Afterburner.
After trying to go lower I started to see a hash boost when going below 250. Going lower, I found that @ 173 and lower my card immediately froze, and less than 185 it would crash and do a VPU reset after a small time.
But at 190 is a sweet spot for me. Hashing increased by 2-3 MH/s compared to anything above 250, and as a bonus the card runs a lot cooler, practically flatlining at 61 degrees at the moment.
It is also pretty effective, pulling that by only using 85w over when sitting idle, or about 1.1 MH/J.

http://imageshack.us/photo/my-images/196/unled1yxj.jpg/

I'm a happy new miner.  

Edit: Pumping core up to 840, my card sits pretty stable at 95.7 MH/s and 62 degrees. Using -w 256 -f 10 makes me go up to 98.4, though windows becomes sluggish then.
I can run at 850 core and get 100 MH/s, but at that point if I so much as touches anything that causes extra GUI operations, the drivers crash.
Before when I clocked core to 850 with standard memory clocks, the card would crash instantly, even when not running the miner. So underclocking memory is a great success I'd say.