JJZolx wrote: > Oh, Christ. I'm sorry I even mentioned it now. This whole HDD/SDD thing has opened a can of worms. I seem to be upsetting people here in the forum and in PM.
The bottom line is, I don't have all the answers. I don't know it all. I know what I want to achieve and I have a pretty good idea of how to get there. I am not "most people". I can only tell others what I have done, how I have done it and why I have done it. I can't possibly comment on whether you can use this specific HDD with board supplied power. I don't own "that" drive. I can't possibly test it to give you a definitive answer. What you need to know and consider before using a single 5V power supply to power the board and a sata drive..... A SSD is an easy choice. The downside is cost, which becomes doubly an issue when considering capacity. Most of the latest gen SSD's that I have used, pull something like 0.5A peak from the 5V rail when writing to the drive and less than 100mW when sitting there doing nothing. Powering a QUAD board and the SSD from a single 5V/2A supply, you shouldn't have an issue. HDD (traditional spinning platter) drives...... The SATA connector is powered by 3 voltages, 3.3V, 5V, and 12V. Most 3.5" desktop drives, (AFAIK), use the 5V rail for powering the drive electronics and 12V for the motor to drive the spindle. Before even getting to power consumption, there won't be a 12V rail without another external supply. Yes, I am aware that there are 2.5" HDDs, which power both electronics and motor from a 5V rail. Yes, I know some of these have low power consumption, maybe as low as a SSD, maybe 2.5W / 0.5A when writing. But there is one caveat I know of that may pose an issue. It used to be the case, at power on, while the motor spins up the platter, the current consumption can spike to several times the "normal operation" peak power consumption. If you intend to power such a drive from a single 5V/2A power supply, it could be that the PS has built-in over current protection, which might be triggered if the board pulls 1A and the drive tries to pull 2A at start-up. Result: the board might not boot if the power supply shuts down. YMMV. I have no intention myself of using anything other than a SSD. If you want to use a 1TB 2.5" SATA HDD and power it and the board from a single 5V rail, store your music library on it, and it all works out OK, then great. But I can't tell you to go ahead and do it. I really don't want to be responsible for anyone spending money on my say so, when I can't 100% guarantee that you what you want to do isn't going to result in a bunch of grief and the need to spend more $$$'s to get it working. ------------------------------------------------------------------------ JackOfAll's Profile: http://forums.slimdevices.com/member.php?userid=3069 View this thread: http://forums.slimdevices.com/showthread.php?t=98544 _______________________________________________ unix mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/unix
