Slashdot Mirror
Intel's New Desktop SSD Is an Overclocked Server Drive
crookedvulture writes "Most of Intel's recent desktop SSDs have followed a familiar formula. Combine off-the-shelf controller with next-gen NAND and firmware tweaks. Rinse. Repeat. The new 730 Series is different, though. It's based on Intel's latest datacenter SSD, which combines a proprietary controller with high-endurance NAND. In the 730 Series, these chips are clocked much higher than their usual speeds. The drive is fully validated to run at the boosted frequencies, and it's rated to endure at least 70GB of writes per day over five years. As one might expect, though, this hot-clocked server SSD is rather pricey for a desktop model. It's slated to sell for around $1/GB, which is close to double the cost of more affordable options. And the 730 Series isn't always faster than its cheaper competition. Although the drive boasts exceptional throughput with random I/O, its sequential transfer rates are nothing special."
Hard for any SATA drive to distinguish itself on sequential transfers, given that SATA is capped around 550MB/s
More data, damnit!
For many (but certainly not all) applications, especially when it comes to UI, what matters is 95% worst performance, not peak throughput. From the Anandtech review, that's where this drive really shines.
Different tradeoffs have to be made for different workloads -- it can't be boiled down to a single (or even a set of) number(s). Some applications are far more tolerant of worst-case performance than others.
Running something at the speed it was designed and verified to run at by the maker isn't overclocking.
Don't get me wrong, I own five discrete SSDs (all currently in active use), and they're all Intel (one G1, two G2s, and two 330s). However, I've been disappointed with Intel of late. It used to be that they came with a premium price, but also dramatically lower failure rates than the competition, and you could usually find them cheaper than the competition if you waited for the right sale.
These days, however, Samsung's failure rates are lower than Intel's, and their price premium is so large that no sale is going to get their larger SSDs anywhere near as cheap as Samsung's. I was hoping that they might make a comeback with a new consumer model, but the 730 is a disappointment in terms of its extremely poor performance-per-dollar and capacity-per-dollar.
I've bought nothing but Intel in the past, because they were the safe bet, but at this point it looks like my next SSD will be from Samsung.
Yeah, anything less than 1 Farad is just ridiculous. No way I would hook my Blaupunkt up to that thing...
I only wish Intel was offering this in a smaller size, say 100 GB. I think a SSD system drive + slow "green" HDD is a great combo in a desktop, and the price premium on this quality of SSD would be easier to swallow if the drive were $110 instead of $250 even though that would be the same $/GB.
tl;dr: these are storage caps, which don't endure the ripple currents that kill filter caps.
Electrolyte decomposition is usually caused by high ripple current, which is why caps pop mostly (only?) when used as filters, as in motherboard DC-DC converters and gadgets powered by wall-wart adapters. In this particular application, the PSU impedance is quite low and the caps are handled by on-board regulators (V=Q/C and all that), so there's no load ripple and the caps just have to sit pretty and charged with insignificant heat losses until the computer is shut down or outage occurs. Maybe that's why Intel didn't even bother to use the solid (polymer) kind.
If these caps dry out due to age or bad quality they just won't hold as much charge for emergency sync'ing, which is still better than ordinary SSDs/HDDs with no caps.
This post contains no rudeness or derision of any kind. All arguments are friendly. Terms and exclusions may apply.
The caps only need to supply enough juice to sync the RAM buffers to flash to ensure consistency of its internal block-mapping metadata (the filesystem should handle the rest through journaling and whatnot). The caps are rated at 35v but let's assume that they're kept at 12v: E = (12 v)^2 * 47 uF / 2 = 3.4 mJoules. Even at full operating load that should last for half a millisecond counting losses, but when power goes out the drive is going to stop serving requests and all it has to do is write that 1 GB buffer to a few flash blocks. More than enough, methinks.
This post contains no rudeness or derision of any kind. All arguments are friendly. Terms and exclusions may apply.
Except those caps are Nippon Chemi-con. High end high quality capacitors made in Japan. And not the kind involved in the bad caps.
Bad cap syndrome happens to the cheap caps - stuff like CapXon (aka CrapXon) and such.
In fact, a lot of bad caps you're finding are the cheap crap ones by the crap manufacturers. You can easily buy them and they will fail.
That's why you'll find people inspecting caps - and seeing if it's Nippon Chemi-con, Rubycon, Panasonic/Matsushita or other Japanese brand. (You can almost generalize it to those whose brands contain "con" in their name are higher quality - from when they used to be called condensers. The cheap brands all tend to have "cap" in their name).
So no, I don't see the caps being the weak point because Intel went and spec'd top-quality caps.
> Although the drive boasts exceptional throughput with random I/O, its sequential transfer rates are nothing special."
But good random access will give you better overall performance in most cases. You rarely need to deathmarch through the drive.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
What you discover with SSDs is that for desktop usage pretty much any drive is "fast enough" and that faster doesn't much matter. I went from a SATA-2 SSD that was fairly slow even for that generation (WD Siliconedge) to a SATA-3 SSD that is fairly fast for this generation (Samsung 840 Pro) and I don't notice any difference. I can benchmark a difference, but I don't see any difference in load times and so on. SSDs are fast enough that they are making themselves not the bottleneck.
That's also why there isn't a ton of interest in the PCIe SSDs. You can get way more performance, but it is a somewhat limited set of scenarios (on the desktop at least) where that would matter.
There is a new standard which will increase SATA speed ( http://en.wikipedia.org/wiki/S... )
Currently, Apple computers use PCIe SSD disks, which increases their performance:
http://www.anandtech.com/show/...
"I'm very pleased with Apple's PCIe SSD, at least based on Samsung's new PCIe controller. Sequential performance is up considerably over last year's 6Gbps SATA drive. Go back any further and the difference will be like night and day, especially if you were one of the unfortunate few with an older Toshiba drive. Internal transfers are quicker, but to actually use the new SSD to its potential you'll really need a very fast external Thunderbolt array - even USB 3.0 can't completely tax it. There's still a lot more investigating that I want to do on Samsung's new controller, but my early results look very promising. It's sort of crazy that Apple now ships a mainstream consumer notebook with a PCIe SSD capable of almost 800MB/s. Now that Apple is off SATA, scaling storage performance should be much easier to do going forward. "
A quality electrolytic capacitor will last a long time.
The ones used here look like Nippon Chemi-Con, rated at 105 C. They'll most likely last forever.
To be fair, an HDD can use its platters as a flywheel to quickly flush its (relatively tiny) buffer. I never did see proof that that was ever done, though.
None used it to flush the cache because it is too risky - the platters are not maintaining a fixed speed (they're slowing down to generate electricity) so writes to platters become tricky as the timing is off which means you can overwrite more than you expect.
Far better to just dump the buffers.
In fact, the electricity generated by the spinning platters slowing down is used to park the heads - it's called an emergency head park because it basically dumps the electricity into the voice coil that flings the heads to the mechanical stops in the park area. It's fairly violent and most hard drives have much less emergency head park life than standard power down (where the drive moves the heads to the parking area in a controlled fashion) life - a drive may have 50,000+ head load/unload cycles, but under 10,000 emergency park cycles.
You can tell because a soft-park makes only the smallest of clicking sounds on a drive when it spins down. But emergency park it and it's a much louder clunk.