The motherboard does have enough PCIe lanes. I will be fine with 1 PSU but I probably will use add2psu when I add another.

GPU mining is definitely not worth it for Bitcoin. I would lose ~$300 annually. I am aware that scrypt ASICs are coming soon but when that happens I'll probably switch to another cryptocoin algorithm such as Scrypt-N or some other ASIC resistant algorithm. For scrypt I should be fine with 8GB of RAM but if I need more then I can buy another 8GB stick. My motherboard supports up to 16GB. (I changed my plan for getting RAM. I am getting a single stick of 8GB ram instead of 2x4GB)

I am probably going to be using these parts to build my mining rig. I just want to be sure I connect everything properly (from the PSU(s)).

My Part List:

Intel Core i3-4130T 2.9GHz Dual-Core Processor
ASRock H81 Pro BTC ATX LGA1150 Motherboard
Corsair Vengeance 8GB (2 x 4GB) DDR3-1600 Memory
Western Digital Caviar Blue 160GB 3.5" 7200RPM Internal Hard Drive
[3x] MSI Radeon R9 270 2GB Video Card
TP-Link TL-WN725N 802.11b/g/n USB 2.0 Wi-Fi Adapter
[3x] Masscool FD12025B1H3/4 81.0 CFM 120mm Fan (1 per video card for cooling)
Crate(s) for the case
Power Button
[3x] PCIe x1 to PCIe x16 Risers [http://www.ebay.com/itm/271373085981] (Each come with a sata to molex adapter for extra power to each video card using a sata connector on the PSU)
Molex to 6 fans adapter [http://www.amazon.com/Phobya-4-Pin-3-Pin-Splitter-Connection/dp/B007S3T4O0/ref=cm_cr_pr_product_top] (so I can attach fans for cooling my video cards)

I do plan to upgrade my rig eventually by adding more R9 270's. Also I ask for suggestions about power supply wattages. I am going to get only 80+ Gold or 80+ Platinum certified power supplies.

PSU 1:
ATX 24 pin to 24 pin connector on motherboard
8 pin CPU power to 8 pin connector on motherboard
1 molex connector to each molex connector on the motherboard
1 sata power connector to the hard drive
1 PCIe power connector to each video card (6 pin)
1 sata connector to each sata to molex adapter for each PCIe riser

PSU 2: (when I upgrade)
ATX 24 pin connector to an adapter connected to the motherboard. Probably this adapter: http://www.amazon.com/Vantacor-Dual-Adapter-Cable-2-way/dp/B00DL3L2J6
1 PCIe power connector to each new video card (6 pin)
1 sata connector to each sata to molex adapter for each new PCIe riser (assuming that I use the same risers)

I read about some people who used 2 PSUs with the ASRock H81 Pro BTC and fried it. I don't want the same to happen to me. Does this setup look correct?

Note: Please don't ask me anything like "Why are you mining with graphics cards?" or "Bitcoin mining isn't efficient with GPUs any more". I am aware that ASICs are necessary for Bitcoin mining now. I will be mining Dogecoin, not Bitcoin. Also please tell me about any suggestions you may have that would improve my build without significantly increasing price.