First Dresser Build - Lighting ?

Hey everyone, first post. I've delved deep into the boards as a lurker and I've been studying. But, I'm still a newbie and need some experienced advice.

I gutted my dresser after work this evening and I know what I'm working with as far as space.

My effective dimensions are 30"W x 18"D x 34"H. I am working on my lighting plans.

I want to know if the 4 pack of 120mm computer fans I bought will provide enough ventilation to keep my box cool with a 150w HPS light.

I'm on a budget and spent a fair amount of it on seeds (Sensi skunk #1, Afghani #1, and Royal Queen Special Kush #1). It's not in the budget to buy an inline fan/filter system AND the HPS light. But I don't want to pump the 70 bucks I could spend on it into CFLs only to upgrade later if I can avoid it. I will be able to upgrade later(possibly the ventilation if I can get by with computer fans for now), but I don't want to put the time and effort into CFLs if I'm going to turn around and rip them out.

For what it's worth, here's a picture of tonight's work.

Look at my vent it might be better on this one. was pretty cheap. 48 total with carbon filter build.

Is that a bathroom "fart fan"? I actually have one of those and consider using it, just worried about how loud it would be.

I'll be searching for your threads with build info now...

Most fart fans have a 3 inch exhaust and the flanges on 2 inch pvc almost snaps right in no effort