3W UV Leds... heatsink and powering question

[robotic]

I'm planning to buy 60 or so UV LEDs. I want to make about 10 units to spread them around the room. The forward voltage ranges from 3.2 to 3.8v. Is it possible to do 3 leds in series and 3 of those series in parallel work? so 3(12v), 3(12v), 3(12v). The current is 700ma so about 2.1A I have a bunch of old PC power supplies I could use which can do 13A on the 12V rail. Can probably power 2 of them if they are close enough to each other...
 
Another option is to buy LED driver... There are two options AC to DC http://www.ebay.ca/itm/85-265V-300mA-600mA-LED-Driver-Convertor-Transformer-Ceiling-Light-Power-Supply-/252064252556?var=&hash=item3ab033428c:m:mDeBfrvHc0FMBdbXGv7CAUg only 650ma (I think that would still work right?)
 
or a DC to DC step-up constant current LED driver.. like this 30W one http://www.ebay.ca/itm/10w-20w-30w-50w-Constant-Current-LED-Driver-DC12V-to-DC30-38V-For-high-power-led-/321461904029?var=&hash=item4ad89f629d:m:mzUySLY-DzUYpp_fJGWZGcg
Will these work?
 
Second question is will this heatsink be okay for 8, 10, or 12 3W UV LEDs? http://www.ebay.ca/itm/1x-Aluminum-Heatsink-300mm-25mm-10mm-for-Led-Emitter-Diodes-High-Power/191931474269?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2763.l2649
 
I could try to add fans to cool them as well. or I would go a cheaper route and get a L bracket aluminum bar and add a PC heatsink to it... not sure if that would work though.

[Audioguru]

3W is probably the absolute maximum IF the heatsinks are perfect and the room is air conditioned. Yours might overheat at 2W or less.
You must use a supply with a voltage high enough for a current-limiting resistor and 3.8V LEDs, maybe 14V or 15V and you must calculate the resistor to limit the current properly even if all the LEDs are 3.2V.

[robotic]

Well 3.5V will be my target i think.  I'm buying some 2W resistors for 2.2ohm (based on the 'led' calculator')

I'm thinking doing the 9 LEDs.  Will that work?

For the heatsink I might try something like what this guy did https://www.youtube.com/watch?v=MeV0ZpYeQ50.

He only used 7 LEDs though =/.   Is it possible to just add a heatsink onto the aluminum L-bracket with some thermal paste and screw it in and then use a cpu fan on it if needed.  BAR -> attach a CPU heatsink -> attach a fan to the CPU heatsink.  Will that dissipate enough heat? on the end LEDS if I place the heatsink in the middle of the bar.

My other option is to mount 3 leds to a CPU heatsink and attach the three heat sinks together... to create a unit.

[robotic]

If I buy a led driver board like say this
30W Driver:
New and high quality, nice design, energy-saving, very strong brightness, waterproof, multifunctional, practical, durable, reusable, convenient.
Driving power: 30w
Model: 10series 3 in parallel
Input Voltage: 85V~265V
Output Voltage: 33-35V
Current:1050mA
Efficiency > 88%
Power Factor >0.98
Operating Temperature: 20~80

Does the 1050mA current matter?  or do I need to find something with 700mA?