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Antec 900 case fans, run off PSU?

Last response: in Systems
January 7, 2009 4:08:46 AM

Hello, just recieved 95% of more hardware for my pc, and this being my first build. Does the 4 fans in the antec 900 that are pre installed run off the PSU(not connected to the mobo?) If so do they connect to the sata connectors? If so only one end fits, whats the other used for? (on the sata connectors.)

January 7, 2009 7:33:49 AM

Most will plug into the MB. The tags are like case_fan1,2,3...You might be able to see on some pictures of yours.
January 7, 2009 10:16:36 AM

OK. So there are 3 types of connection setups fans normally use.

1) A 3 pin connector with 3 cables leading into it that goes to the motherboard. 2 for power and 1 for data.
2) Others use a 4 pin molex(not SATA) with only 2 cables for power.
3) Others (the best IMHO) are those with a 4 pin molex with 2 cables for power and a small 3 pin motherboard connector with only 1 cable for data.

The data cables for option 1 and 3 simply allow for a fan speed readout. The fan speed can still be set manually (if blind about the exact speed) without it.

If your fans are option 1 connect them to the motherboard. However I somehow think they are either option 2 or 3 in which case they will use the 4 pin molex connectors. Option 2 or 3 is likely because most motherboards only have 3 fans connectors including the CPU fan connector yet the case has 4 fans.
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January 7, 2009 6:47:41 PM

January 8, 2009 9:08:35 AM

The four fans each have a molex connector, each.

So can I get 2 leads/cables each with 3 molex connectors on them. (one wile have 3 fans on one cable and one will only have 1 fan on the cable, so 1/3 molex connectors used.) THEN do i connect those two cables to two differnt case_fan slots (say 1 and 2.) on the motherboard?

My question is, what happens if you dont connect the cables to the mobo via the case fan conncetions? And only power from the psu is added, why does it need to be connected to the mobo when there just fans?
January 8, 2009 7:13:12 PM

I may be wrong (i haven't built my rig yet) but i believe connecting the fans to the MB will allow the computer to adjust the fan speeds higher and lower as needed. ie. putting more stress on the system would require higher fan speeds to prevent any overheating or damage to your components.
January 8, 2009 7:23:18 PM

I also have the Antec 900 case. I couldn't figure out how to get the fans connected to the mobo... so i didn't. They have a molex connecter for power to the fans, but then the fans all have a manual switch for speed. The switch has a setting for L (low) M (medium) and H (high) and the default setting on mine were all LOW.

Ive been running my comp q6600 OC to 3.0 GHz with a asus HD 4850 gpu stock OC to 680/1100(if i remember correctly) and the temps all seem very good. So maybe the low setting is good on the case if your not going crazy with gpus.

If someone knows how to get the fans connected to the mobo i'd be interested in knowing how. Im sort of a noob :) 

Edit: Bingy after re-reading your post it sounds like your talking about trying to connect the 4-pin floppy drive power connector on the end of your daisy chain of fan power connections to the cpu_fan slots on the mobo. I don't think it will fit and/or work... Sorry hard to explain, but if your asking what im thinking you'll understand.