$1600 high end gaming build

Get a i5 3570k.
Or else your Mobo is a waste.

And if you can, then get a Bigger Monitor with 2560x1600 Resolution or more.

$1600 is not a budget build, so you should buy a 3570k not 3570. One day you will want to overclock your CPU (considering you want the UD3H mobo).

700W is overkill, unless you know you will buy a second 7970 in the future.
On 1080p, why not get a 7950 or 670; then you can buy a 120/128gb SSD for OS and programs. You won't regret it, the speed is awesome.

Your monitor is great for gaming. But I kinda agree with Sumukh...with a 7970 you might want a better monitor...1200p or 1440p. However, if you don't ..your Asus is still great.

1.Can you please suggest a motherboard or even just a quality brand as I don't really want of overclock my i5.
2.How superior is GeForce to Radeon HD? In Australia the 670 is around $100 more than the 7950.
3. I don't really understand how the faster speed of a SSD will benefit m.

If you can help with any of these it would be much appreciated.
Thanks.

1. You chose a Z77, which is for overclocking. Buy a H77 mobo, it can't overclock but it's cheaper. Just search for mobo.

2. People always argue over AMD or Nvidia. The 670 is better then the 7950.(can't dispute that) The big difference is that Nvidia is smoother (less latency) and has PhysX (for greater details in some games) whereas AMD has good prices. What are the average prices of 7950 and 660ti in AU?

3. The SSD will allow applications to open in a snap. If I double click on a program, the program will pop up much faster than if I had my programs on a HDD. Also, working in Photoshop...it applies things and saves faster than HDD. Typically, people put OS and all programs on SSD, then save data to a HDD. You really should consider this. Also, prices for SSDs have fallen so much that it is easy to get a 120/128gb SSD for $100usd.

Thanks, I didn't know the difference between z77 and h77. Is it acceptable to have a mATX mobo as I am finding it difficult to find any ATX h77 mobos. If so, is this ok : ASUS P8H77-M PRO Motherboard?
The 7970 retails around $330, while the 670 goes for about $420.

Before I thought mATX wouldn't perform as well as ATX, but I was wrong. Usually a mATX is the same but with less PCIe slots(can't use two GPUs) or less SATA ports(only matters if you have many HDDs and peripherals). If you have one HDD and one GPU then mATX are great. The only drawback is that it might be tighter cable management but probably a non issue.

The ASUS P8H77-M PRO looks fine. It'll get the job done well. I would feel confident with it.

Given the prices, I would buy a 7970 for $330 with no reservations! What brands can you get?

Sorry I meant a 7950. 7970 is about 420. I am considering changing to a 7950 as I do not have a monitor over 1080p and I can't afford to get one. Thanks for mATX info, and as I don't have multiple HDDs and probably won't crossfire in the future, it will be fine. I was thinking of a Gigabyte 7950 3GB, but the available brands are ASUS, Gigabyte, Powercolour and Sapphire.

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: Intel Core i5-3570 3.4GHz Quad-Core Processor ($209.98 @ SuperBiiz)
Motherboard: ASRock H77 Pro4/MVP ATX LGA1155 Motherboard ($79.98 @ Outlet PC)
Memory: Mushkin Blackline 8GB (2 x 4GB) DDR3-1600 Memory ($35.57 @ NCIX US)
Storage: Samsung 830 Series 128GB 2.5" Solid State Disk ($112.98 @ Newegg)
Storage: Seagate Barracuda 2TB 3.5" 7200RPM Internal Hard Drive ($109.99 @ Amazon)
Video Card: Gigabyte Radeon HD 7950 3GB Video Card ($289.99 @ NCIX US)
Case: Corsair 500R Black ATX Mid Tower Case ($101.60 @ Mac Connection)
Power Supply: SeaSonic G 550W 80 PLUS Gold Certified ATX12V / EPS12V Power Supply ($85.99 @ Amazon)
Optical Drive: Asus DRW-24B1ST/BLK/B/AS DVD/CD Writer ($19.99 @ Newegg)
Monitor: Acer G236HLBbd 60Hz 23.0" Monitor ($109.99 @ Newegg)
Operating System: Microsoft Windows 7 Home Premium SP1 (OEM) (64-bit) ($89.98 @ Outlet PC)
Total: $1246.04
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2013-01-12 17:18 EST-0500)

Found the ATX H77 motherboard you were looking for, if it really matters. Added the monitor and OS. The PSU is a good value for a Gold certified and modular one and from a reliable company. You could go cheaper with an XFX 550W for ~$54 Bronze non-modular.

Can't find that motherboard in Aus. Already looked. Nor the RAM but I could probably find an equivalent. Is 1600mHz RAM ok?
The damn psu is double the price here. Does the power a psu delivers drop as it ages?
Thanks for trying, but Aus part availability and price sucks.

Yeah, buy 1600mHz RAM. It's the sweet spot.

About the GPU, the 7950 is a great card for 1080p. (I use a 660ti, which is the same level and play on 1080p.) You don't really need 3GB. You can find 2GB for cheaper. If you are deciding between brands, Asus Gigabyte Saphire, are all good.

PSUs should hold up over time. Just make sure it is efficient, at least 80 bronze.