On 11/26/2010 1:11 PM, Krunal Desai wrote:
What about powering the X25-E by an external power source, one that is also
solid-state and backed by a UPS? In my experience, smaller power supplies tend
to be much more reliable than typical ATX supplies.
I don't think the different PSU would be an issue, The supply you've linked
doesn't seem to care about linking grounds together.
or even more reliable would be a PicoPSU w/ a hack to make sure that the power
is always on.
Has anyone tried something like this? Powering ZILs using a second, more
reliable PSU? Thoughts?
I hacked up a PicoPSU for robotics use (running off +24V and providing +5/+3.3); your
"always-on" should be as easy as shorting the green-black wires (short Pin 14
to ground) with a little solder jumper.
But wouldn't you need some type of reset trigger for when the system is reset?
Or is that performed by the SATA controller?
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Frankly, adding something to the controller card (and, that's where
you'd have to put it, since just providing UPS power to the SSD wouldn't
be sufficient) is going to be a nightmare, and I would suspect
ultimately creates more unreliability and failure than it solves.
I've gone to using an OCZ Vertex 2 EX, which has a supercapacitor
on-board to enable full consistency in case of a power outage.
OCZSSD2-2VTXEX50G
It's not cheap ($800 / 50G), and you *really* want to make sure you get
the 4k alignment right, but I haven't had any real problems with it.
I haven't had a chance to test a Vertex 2 PRO against my 2 EX, and I'd
be interested if anyone else has. The EX is SLC-based, and the PRO is
MLC-based, but the claimed performance numbers are similar. If the PRO
works well, it's less than half the cost, and would be a nice solution
for most users who don't need ultra-super-performance from their ZIL.
The DDRdrive is still the way to go for the ultimate ZIL accelleration,
but it's pricey as hell.
--
Erik Trimble
Java System Support
Mailstop: usca22-123
Phone: x17195
Santa Clara, CA
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