[SOLVED] GPU Power adapter

Jan 10, 2022
27
3
35
0
Ok so guys Im currently running a pc with no 6pin gpu power cable. Therefore Im using a molex to 6pin adapter to power my GTX 960, I decided to use molex instead of sata because I heard that sata to 6pin tend to fail more. Im currently unable to buy a new psu. Anyways my question, is 1molex to 6pin enough for a GTX 960?
 

lordmogul

Distinguished
Jun 14, 2014
515
22
19,365
189
While FSP is a proper brand (they make units for big companies like Dell or HP, manufacture for 3rd parties and also sell under their own brand), 300W is really pushing it (I have a 350W unit that can deliver 336W over the 12V rails, but it's still not a big unit)

Also agree on the Molex vs SATA for the adapter. SATA allows for 1.5A per pin or 4.5A total (cause it uses 3 pins per rail) that still gives only 108W over the 12V line, even with a 2to1 cable, Molex is rated for 11A (264W), which is enough for the 150W on the PCIe plug.

Still, having to use an adapter means the PSU is not build for that kind of load, which is why the PCIe plugs are typically omitted on smaller units.

The GTX 960 is rated for 120W TDP.
Add your CPU (lets assume something typical, so 80W), motherboard (maybe another 40W), RAM (lets say 20W), drives (take around 8W per drive) and even with the most careful setup that's another 140-150W, which brings the system to 260-270W, which is around 85-90% of the total 300W rating, which is split among the different voltages.

After checking the unit, you're limited to 240W on the 12V rails, which are 8A and 13A (which is and 96W and 156W) so you can't even be sure that you'll have the 120W (plus what your drives use) available for the GPU.
Looks like it's coming from an acer prebuild system.
 
A PSU not having the necessary connections for a gpu means that it's not meant to power said GPU. There is no way around it.

Adapters are a huge no. Fire hazard and burnt/failing components on the way. Molex and SATA are not meant to power a gpu.

The only adapter that is recommended is 2x6pin to 8pin.

What is the exact make and model of your PSU?
 
Reactions: Phillip Corcoran

lordmogul

Distinguished
Jun 14, 2014
515
22
19,365
189
While FSP is a proper brand (they make units for big companies like Dell or HP, manufacture for 3rd parties and also sell under their own brand), 300W is really pushing it (I have a 350W unit that can deliver 336W over the 12V rails, but it's still not a big unit)

Also agree on the Molex vs SATA for the adapter. SATA allows for 1.5A per pin or 4.5A total (cause it uses 3 pins per rail) that still gives only 108W over the 12V line, even with a 2to1 cable, Molex is rated for 11A (264W), which is enough for the 150W on the PCIe plug.

Still, having to use an adapter means the PSU is not build for that kind of load, which is why the PCIe plugs are typically omitted on smaller units.

The GTX 960 is rated for 120W TDP.
Add your CPU (lets assume something typical, so 80W), motherboard (maybe another 40W), RAM (lets say 20W), drives (take around 8W per drive) and even with the most careful setup that's another 140-150W, which brings the system to 260-270W, which is around 85-90% of the total 300W rating, which is split among the different voltages.

After checking the unit, you're limited to 240W on the 12V rails, which are 8A and 13A (which is and 96W and 156W) so you can't even be sure that you'll have the 120W (plus what your drives use) available for the GPU.
Looks like it's coming from an acer prebuild system.
 
Jan 10, 2022
27
3
35
0
While FSP is a proper brand (they make units for big companies like Dell or HP, manufacture for 3rd parties and also sell under their own brand), 300W is really pushing it (I have a 350W unit that can deliver 336W over the 12V rails, but it's still not a big unit)

Also agree on the Molex vs SATA for the adapter. SATA allows for 1.5A per pin or 4.5A total (cause it uses 3 pins per rail) that still gives only 108W over the 12V line, even with a 2to1 cable, Molex is rated for 11A (264W), which is enough for the 150W on the PCIe plug.

Still, having to use an adapter means the PSU is not build for that kind of load, which is why the PCIe plugs are typically omitted on smaller units.

The GTX 960 is rated for 120W TDP.
Add your CPU (lets assume something typical, so 80W), motherboard (maybe another 40W), RAM (lets say 20W), drives (take around 8W per drive) and even with the most careful setup that's another 140-150W, which brings the system to 260-270W, which is around 85-90% of the total 300W rating, which is split among the different voltages.

After checking the unit, you're limited to 240W on the 12V rails, which are 8A and 13A (which is and 96W and 156W) so you can't even be sure that you'll have the 120W (plus what your drives use) available for the GPU.
Looks like it's coming from an acer prebuild system.
yeah its an acer veriton from around 2013 , it has ASUS STRIX GTX 960 2gb an i5-4570, 8gb ddr3, 120ssd and 2tb hdd. Btw I did reduce the power limit of gpu using MSI afterburner and only lost like 1 or 2 fps, I make sure the gpu does not go over 90 watts usage , thas 45 watts from pci express and 45 from Molex to 6pin adapter.

I would like to know what the real concern is, The PSU not being adecute for this componets or the chinese adapter ( worried that the cable could melt) and how long can I use this set up in order to save up for an adecute PSU , the acer motherboard seems to have a 24pin plug so it wont be hazard to deal with
 
Last edited:

ASK THE COMMUNITY