GQmer Nomi :
the probleme is i have tow radiator in 900d case if i want change the motherboard or gpu with no water out the quick disconnect well help or not ?
If you want to do that you surely can but IMO it is a serious waste of money that you could use elsewhere, but it is your money, like I said these quick connectors are not cheap.
Some other uses of quick disconnects:
http://koolance.com/help-quick-disconnect-shutoff-couplings
http://www.maximumpc.com/article/ho..._techniques_detailed_and_constructed?page=0,1
And some advice on tested quick disconnects covering some of the newer brands on the market, at the time of the review:
http://www.xtremerigs.net/2013/07/02/2013-quick-disconnect-roundup/
Caution: These type of loop additions, quick disconnects, flow meters, hard 90 degree fittings, motherboard water blocks, water blocks for multi GPUs, etc., increase flow restriction and add strain to your water pump, so you need to educate yourself fully on what you're getting yourself into with the added side effects on flow restriction.
These may seem to you to be an Ohhh Ahhh convenient water cooling accessory, but multiple uses of them is going to increase your flow restriction.
So don't go crazy with these things in your loop or loops and get the highest flow rate and least flow restriction disconnects you can find.