Computer fans

What are the cfm's of computer fans?

I am trying to figure out what/ how many I need, but I cannot without any specs. regarding cfm/mm size.

what size is your grow room

Room size is in the works.
Which is why I am concerned for ventilation.

My space is a upstairs crawlspace of a 1.5 story house.
Right-angle triangle.
The room is 5'4" high, by 7 wide, by 1/2 the length of house.

I am currently vegging in there with CFL's.
No real exhaust ventilation.
Just 2 fans blowing cfl heat away and up.
Leave crawlspace door open if concerned temps won't stay in the norm for that day.
With snow on the roof (extra insulation) it gets to high 70's ambient near plants.
I am learning that cfl's probably put out the same heat as HPS watt for watt.
But possibly even harder to control since the heat is not from one source, but many.

Hoping to use a 400w or 600w HPS for flowering for one source heat issue.
Maybe steal some 6400k cfl's from veg'rs for corner lighting if heat is not an issue.

So, now I want to make a flowering space in same room.
Going use and old 32" door and cut-off the low height area that is useless.
This will make it so tallest wall is 5'4, shortest wall is 32", floor space approx 4' wide.
As long a length as I need it (without getting rediculous for my lighting and consumption).
Maybe just the doors length itself.
Maybe 2 doors long. (will increasing room size lower temps also?, or just mean more venting needed?)

Make a cheap flimsy false wall to block flowering plants from veggin light.
Duct tape and mylar the inside.
This would give me 24hr access to my veg'rs, and 12hr access to my flowers.

I would also like to keep this as stealth and simple as possible.
No loud fans. vibrating walls, obvious duct work running through the house, etc.
LOL.

I have a buddy willing to help me with the project, since I cannot do it all.
But I also do not want to eat up all his time on this.
lol.

I was thinking to vent with 3.25" venting from crawlspace to the attic.
This should be able to squeeze between the outside roof and the upstairs ceiling, hopefully.
Give or take a nail.

Since a 2x4 is not actually x4, I could not go this size.

So what is best for my situation on venting?
Multiple pc fans?
A 8" vented hood or cooltube, 8" inline fan, slammin into 2x3.25" vents?
LOL.
Again, I would prefer stealth.
I assume multiple pc fans would be quieter.
And temp. controlled pc fans are probably a bonus too. (when snow is not on roof, temps will currently drop to 60's)

Any thoughts?

PS. I just plugged in a cold-mist humidifier, and unplugged my humidifier.
This should also help me a degree or 2.

i use a computer fan, i cut the wires and hooked htem up to a plug that i didnt need. works fine for me

So if I have a space of 106 cubic feet. (my guess of 1 door length 7' long)
Will 2 PC fans keep up to a 600w hps?
I assume I would need 4-6 fans.

Are HDD fans more efficient than the cpu or case fans?
Could line the top corner of ceiling with HDD fans mounted to each other in a row.
I assume these are approx. 2x2" fans.
Even smaller venting may be easier for me to shove through the roofs bracing.

I am confused on what is best.

Most standard pc fans range 65-80 cfms.

I have one that is 120v 200cfm for a computer and home theater tower.