Quote from: niknik83 on February 11, 2014, 05:02:16 PM

3L is a lot. where are you based? make sure that your electrical setup can take the load coz that much money will add 2-3kW to your load (very rough estimate)

Anyways, the main component you should focus on is the GPU. While the 7990 is the fastest in terms f hash rate/card, it is too expensive and as a result not the best in terms of Rs./khash.

For 3L, you can build 3 rigs (unless you can get your hands on some powered risers) - Config:

GPU: R9 280x ~23-25k (gives you about ~700 kh/s) 2-3 on each rig
MB: Gigabye UD3 ~9,500
CPU: AMD Sempron 145 ~1,800
RAM: 2GB Kingston/Corsair ~2,200
PSU: Seasonic/Corsair/CoolerMaster
650w ~3.5-4,000 - will barely take 2 280x's (i wouldnt risk it)
850w ~9-11,000 - will take 2 280x's
1000w ~ 12.5-14,000 - will take 3 280x's

For the PSU, you can choose to go with multiple 650w's on each rig in order to reduce cost. Use a 2PSU cable.

@archit this is very good info here...i myself use exactly these component PSU is 850 watts with 2 r9 280x (one of them is sapphire toxic)
i measured the power the rig uses only 620 watts on full load..room for one more r9 270x