riser only 12 volt problem

[trippcheck]

i have  a server psu
output only 1200 Watt 12 Volt

i connect the riser to 12 volt
gpu fans not spinning by power on rig

is riser direct connect to normal PSU with 12 and 5 volt
fans are spinning

need the powered usb riser 12 and 5 volt?

[KougarLOB]

You answered your own question.

Yes, the card needs voltages other than 12.  Some risers, generally the higher quality ones, regulate the voltage down from a single 12v source.  These have a 6-Pin Molex Mini-Fit Jr (PCI-E) connector.  Others utilize a mix of 12 and 5v and use a 4-Pin connector.  The 4-Pin styles typically consume more energy than the 6-Pin ones - even without a card connected.

Example of what I'm using:  http://www.ebay.com/itm/131962699972
Do not use the included SATA-to-6pin.  You will burn up the SATA connector.  Extract the pins and reuse the plastic 6-Pin if you build your own cable.

[uray]

riser use 12v and 5 volt, unless you are using 6-pin powered riser which has stepdown converter built-in for 12v to 5v

[superminator]

You answered your own question.

Yes, the card needs voltages other than 12.  Some risers, generally the higher quality ones, regulate the voltage down from a single 12v source.  These have a 6-Pin Molex Mini-Fit Jr (PCI-E) connector.  Others utilize a mix of 12 and 5v and use a 4-Pin connector.  The 4-Pin styles typically consume more energy than the 6-Pin ones - even without a card connected.

Example of what I'm using:  http://www.ebay.com/itm/131962699972
Do not use the included SATA-to-6pin.  You will burn up the SATA connector.  Extract the pins and reuse the plastic 6-Pin if you build your own cable.

One question, can I plug a connector molex 6-pin in a 4-pin riser with an adapter?. What about voltajes?. I don’t have more 4-pin connectors in my power supply.

Best regards.

[Zorg33]

No. 5V is needed for risers with molex 4pin connector.
You have to use 6pin risers that only need 12V.

[swogerino]

CompTIA A+ certified technician here and I want to answer the question by first telling everyone here that the PSU simply converts AC into DC and the motherboard cables only supply three different rails, 12 v ,5 v and 3.3 v . There is no other voltage, keep in mind a +-10% is the maximum tolerance.

Based on that , riser which use a 6 pin needs 12 v and these are also the most stable risers for the moment.