3.3v line is probably for newer technologies. No known HDD uses the 3.3v line but maybe SSDs use them.
SATA power plugs have many pins because they need multiple pins for power because one pin is too small. I think each power wire uses 3 pins or something like that. Also a few more pins are used for hot-plugging technologies.
http://superuser.com/questions/98274/why-are-there-so-many-pins-on-a-sata-power-connector
why not just keep the legacy 4 pin Molex like some of the early SATA HDDs do?
why not just keep the legacy 4 pin Molex like some of the early SATA HDDs do?
Because it is large, held in only by friction, and not good for hot swapping.
New technology
Hot-plugging capabilities
Slim
Universal (same connector for 3.5 and 2.5 form factor)
a SATA Power is larger; Thinner but wider and itself held in by friction. I actually have had many SATA HDDs stop working because the SATA cable or the power cable wiggled loose with vibration of the HDD; Don't have that problem with IDE connectors or Molex plugs
The SATA power cable is designed to have a thinner profile. They are also designed to have a clip on them. Cables not having a clip on them are out of spec and prone to the problems you have noticed. Molex cables can sometimes bind to the drive resulting in a very difficult removal that may result in damage to the cable or the drive. Most modern, even going back five years, power supplies have SATA power cables and no Molex cables.
The SATA power cable is designed to have a thinner profile. They are also designed to have a clip on them. Cables not having a clip on them are out of spec and prone to the problems you have noticed. Molex cables can sometimes bind to the drive resulting in a very difficult removal that may result in damage to the cable or the drive. Most modern, even going back five years, power supplies have SATA power cables and no Molex cables.
yeah, the thing I don't like about molex is that they are hard to remove and don't have a good "click".
Budget box PCs from five years ago use even more budget power supplies designed from an even longer time ago.
Multi fan power supplies have been around since the 80's. $50 is still rather low budget for a power supply.
The USB card is likely suffering from a dirty power feed or interference caused by some of the drives.