1) Can I attach 2 120mm fans to GPU headers, given I have adapters? Will a XFX 580 be able to power them?
2) Is it possible to attach a downdraft air cooler like the CM Geminii 4 to a gpu? I see they have an offset so it appears it wouldn't interfere with the mobo.
3) Is $40 a steal for a used Noctua NH-D14?
1) Yes, you can repladce stock GPU cooler fans with 120mm or 90mm or 80mm fans. I've done it several times. Just remove stock shroud and fans then install new fans with zip-ties.
2) Yes, but just changing the stock fans will probably give you good cooling. Also remove all PCie back slot covers to improve case front to back airflow. You might find the below link to how airflow works and how to optimize it in your case of interest. https://www.overclock.net/forum/246-...l#post22319249
3) Yes, $40 for NH-D14 is a good deal, but you might need to buy new updated mounting kit. If owner is original owner Noctua will give them a new mount, but usually not free to 2nd owners so might be worth asking owner to request updated mounting kit to be included in purchase.
Phanteks Owners ClubWays to Better Cooling
i7 980 @ 3.55GHz =PH-TC14PE w/2x TY-143 fans =Crucial Ballistix 3x4GB =GA-X58A-UD5 =ASUS GTX580 DirectCU II =Enermax Modu84+ =Define R2 w/3x TY-140 case intake fans; all PWM controlled by CPU fan socketPhanteks Enthoo Primo MoBoRampage III ExtremeCPUi7 980X @ 4.0GHz =R1 Ultimate w/2x TY-143 fans =Dominator GT 6x2GB =Rampage III Extreme =ASUS GTX580 DirectCU II =TX850 =Enthoo Primo w/ custom castor base