i just got a new case fan for my PC and need to know how tohook it up. the fans a vantec temp controlled 80mm that comes with two connectors one for the power its a 2 pin and one for i think RPM its has one yellow wire i hooked up the 2 pin to one of my power plugs off my HD power cable but im not getting any RPM readings off my MBM5 software does the yellow wire go to the casefan1 plug on my MOBO to be able to read RPM? X/Technology Pentium 4 @ 2.8 Ghz 533Mhz FSB 512K 512MB PC2100-266MHZ DDR Ram GeForce FX5700LE 256MB DDR 8x AGP DVI TV out 3D PCI Sound Pro Integrated Audio WD Caviar 40GB Ultra 10

To get a reading in MBM I believe the fan needs to be connected to one of the fan headers on the MBoard.

ok but does the MB header supply power too or just RPM read out X/Technology Pentium 4 @ 2.8 Ghz 533Mhz FSB 512K 512MB PC2100-266MHZ DDR Ram GeForce FX5700LE 256MB DDR 8x AGP DVI TV out 3D PCI Sound Pro Integrated Audio WD Caviar 40GB Ultra 10

After rereading your original POST I am wondering if I am unaware of something. Why did you connect the fan to your HD? To answer the other question the MBoard headers supply the power and depending on the MBoard may monitor the fan speed. If you have a tempurature controlled fan there is no need to monitor the speeds. The more important issue is where to locate the temperature sensor. The reason for needing the fan speed monitored is if you have an adjustable speed fan you can play with the speeds to quiet the system and still maintain proper temps. I see no advantage to monitoring if you can't control the speed. Just monitor the CPU and system temps, keeping them within acceptable limits.

sorry for the confussion i didnt hook it up to the HD i just hooked it up the the molex plug on the power cables.so the one single yellow wire supples power and the abilty to pick up RPM off the MB.i like to see the RPM of the fans so i know there running is why i ask and thank you for your time X/Technology Pentium 4 @ 2.8 Ghz 533Mhz FSB 512K 512MB PC2100-266MHZ DDR Ram GeForce FX5700LE 256MB DDR 8x AGP DVI TV out 3D PCI Sound Pro Integrated Audio WD Caviar 40GB Ultra 10

There are adapters to go from standard molex to the type needed to connect to the MB headers. I have bought fans with those included. You may not have enough fan headers on the MB anyway. MBM is no longer supported so if you have a new board you may not get it to work right. As far as the two connectors that came with your fan go I would say that if one of them will mate up with the MB fan header then that is what it was intended for.