Miner Build x2

[namley]

Building 2 new rigs as a short term investment while the difficulty rate for mining is still someone feasible

Here is the setup, wondering if anyone has some positive tips on the hardware before I click the buy button.

Setup
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Motherboard - ASRock 890FX                    http://www.newegg.ca/Product/Product.aspx?Item=N82E16813157208
CPU             - AMD Sempron 140               http://www.newegg.ca/Product/Product.aspx?Item=N82E16819103698
RAM            - Kingston 1GB 240-Pin           http://www.newegg.ca/Product/Product.aspx?Item=N82E16820134784
GPU(s)         - 3xPowerColor AX6870          http://www.newegg.ca/Product/Product.aspx?Item=N82E16814131373
PSU(s)         - 2xhec X-Power Pro 600        http://www.newegg.ca/Shopping/ShoppingItem.aspx?ItemList=N82E16817339025
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Thank god for a nice tax return,
I plan on building 2 of these rigs.

Total Rig Cost $976.31 Shipped
Grand Total $1952.61

With an overclock on those 6870's I should be able to force about 450MHash's out of the cards, hoping to average
2.5-2.7 GHash/s

Any tips or suggestions would be much appreciated.

[kjj]

GPU(s)         - 3xPowerColor AX6870          http://www.newegg.ca/Product/Product.aspx?Item=N82E16814131373
With an overclock on those 6870's I should be able to force about 450MHash's out of the cards, hoping to average
2.5-2.7 GHash/s

Not even close.  You'll top out around 300-310 per card.  Odds are good that some of them won't even reach 270.

[namley]

Thats all!? I get 304 with my 5830 overclocked.

[namley]

According to the Hardware comparison chart, https://en.bitcoin.it/wiki/Mining_hardware_comparison

Thats pretty accurate, wow. May as well, save $500 and go with 5830's