That looks like it will last even more than a couple of years
I wasn't following all the newest gear lately, so just some general reliablity tips from me...
Go to tomshardware and have a look at the cpu (and other) comparison charts esp. the photoshop benchmarks. That way you can get the components that provide the most bang/$. i7 will be awesome. Get a good CPU cooling rig; most products are heaps better than what intel supplies w/ the processor. Make sure the cooler sits properly on the cpu & use good thermal paste (Artic Silver 5 is good). Install cpu temperature monitoring and keep an eye on it when running the system on full load during the first few days.
Also pay attention on the other components needing cooling (chipsets, GPU, PSU, RAM, HDDs), having enough airflow, etc.
I have a three yo system (xp 64bit) w/ 4GB RAM, but scratchdisk still gets used, so since most motherboard chipsets have RAID controllers now, configure two HDDs (or just parts of them, say 2 x 150GB) to run in stripe (raid 0) mode. That will give nice swap speeds even when your individual drives are not exactly speed demons (NB: don't store important data on them). Put those on the 'inside' of platters for even better acces times (rotational speed).
Western digital raid edition enterprize level hard drives have great MTBF numbers + good warranty as well, others may like other brands (also forget SSD).
Quality DDR3 for RAM. It is worth researching very closely how will the RAM play w/ your motherboard/CPU combination, what are the optimal/stable speeds, etc.
In terms of stability the motherboard and the PSU are the most important components. Most everything is integrated on motherboards now, so make sure you check out all the available reviews of your chosen motherboard re those components and make sure there are reliable, tested drivers available for all of them for your choice of OS.
Get the best quality PSU you can afford, online calculators for optimal wattage, 750-1000W is a safe bet. One powerful 12V rail is better than multiple rails.
Get a PSU w/ a 80-85% or more efficiency rating.
Expect to run out of HDD space eventually so consider an eSATA (4 or more bays) enclosure. Good motherboards often come w/ multiple eSATA ports and port multipliers or just buy a RAID card w/ the enclosure.
After three years I have 3x 500GB, 3x 1TB drives and three smaller ones in my rig and I will be running out of space again (mostly b/c I mirror some of them).
Think about your display first and then match a GPU card to that. You won't need a top-of the line card for photoshop, just something 'windows compatible'.
Get a surge protector or even better an UPS witch will match your system load (there are online calculators for that too) and provides 'clean sinus waves'.
Get a large, sturdy case to hold all this and to have sufficient air-flow. Tidy up the internal cabling for this reason as well. Same cases don't have enough space for large power supplies. Some cases come w/ 'slide-out' motherboard trays, that's great when installing components. Get cases w/ thumb screws. Clean yor components of dust at least 2x/year, but never w/ compressed air. Check your fans regularly and apply grease or swap them out when failing...
Look for ways to reduce noise and vibration in your case from hard drives and fans...
I know it's a cliche, but even if you build RAID arrays it's not a backup, so store a copy of your data off-site.
Don't install all kind of programs and hardware on your production workstation, don't even connect it to the internet, just for must-have system updates. Use a separate pc for trying out new stuff and surfing. Nevertheless run antivirus software all the time...
Check out the enthusiast overclocker forums for your HW info and tips/gotchas & make sure all the component in the system play nicely together.
Learn your bios settings (FSB, multipliers, volts and all that).
That gear is so overclockable not only b/c of the quality, but because it is well matched/tuned to begin with, but I would actually remommend to underclock your rig slightly for even more stability (eg lower voltage to the cpu). Speed will always be there when/if you really need it, but overclocking (=heat) at all times will deteriorate the life-span and reliability of the chips.
HTH,
Sz
