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Why Not Solid State Hard Drives?
waterlogged asks: "I was just wondering if anybody has heard of a cheap ram based network drive? Seems to me with the ram prices being at about US. $12.00 for 128 megs that someone hasn't developed a battery backup version of this to plug into a network or even a bus. A gig worth of 8ns seek time storage for $120 anyone? That would just about eliminate any wait in loading programs."
BigSlowTarget asks: "There are some previous articles on Slashdot about vendors selling solid state drives, but they all seem to be quite expensive - particularly given the slide in the cost of memory. Has anyone hacked together a solid state drive to take advantage of $60/GB memory prices? I'd really like to be able to boot and run at solid state speed without spending thousands."
Jah-Wren Ryel asks: "In case you haven't noticed, RAM is incredibly cheap, you can put a gigabyte of PC133 RAM into your machine for less than $60. A year ago, that would have cost more like $600. So now it is feasible for one to have a 10-15GB RAM disk, except for one thing - most motherboards won't support more than 2GB total (4 dimm slots x 512MB per dimm). It seems like it wouldn't be too hard to design a PCI card to hold 20-30 dimms and make that available through a hardware windowing scheme (like EMS/EMM back in the old 16-bit days). With the right drivers it could be used as a big RAM disk or for buffercache. Is there such a product out there? The closest I have seen are solid-state disks that sit on the other end of a scsi bus, are too expensive, and aren't anywhere near as fast as a PCI implementation could be."
So what technical details (and the issues of volatile data and price) may be preventing the construction of RAM based drives, and is there anything else that may be preventing some entrepreneurial soul from bringing such a thing to market?
Umm.. i hate to be the only pesemist here, but if you build a drive outa plain old SyncRAM, what do you do when the power goes out? I mean, sure there's UPS and the like but, still.
It'd be great for swap space or temp storage... but if that's the case, PUT THE RAM ON THE MOTHERBOARD DUMMY! and if anything, create a ramdisk from that ram!
I wanna BOOT from it.. I'd love to fire up my box hand have the "login:" sitting there after i blink!
couldn't you just use a battery?
> RAM is now cheaper when it comes to memory-per-unitofcurrency than hard drives
Huh? Where are you buying your RAM and/or hard drives?
60 GB hard drives are available for less than $120-- under $2 per GB.
RAM is approximately $75 per GB.
That seems a bit off from what is claimed.
Do the math... hard disk are still 100 times cheaper that RAM.
Oh, and FWIW, you can buy solid-state battery backed RAM based hard-drive technology; you've been able to for years.
$20 gets you about 256 MB of ram. $200 gets you about 75,000 MB of HD space. Ten times the price gets you 300 times the MBs. What are you smoking, and can you give some of it to my credit card companies?
I never quite thought I'd see this in my life time, but RAM is now cheaper when it comes to memory-per-unitofcurrency than hard drives.
It is? RAM is around $50 for a gig, a hard drive is $300 for 100 gigs, or $3 per gig. RAM doesn't look cheaper to me...
And I'd be a Libertarian, if they weren't all a bunch of tax-dodging professional whiners.
Berke Breathed
While yes, $200 will get you about 80GB of 5400 RPM Hard Disk, a quick look at thechipmerchant.com shows...
PC 2100 DDR 32X64 [256MB]
$50.00
PC 2100 DDR 32X72 [256MB] ECC
$57.00
KINGMAX PC150 32X64 [256MB]
$44.00
PC133 64X72 [512MB] ECC Reg.
$86.00
Rambus is a bit more, but still cheap compared to a year ago
PC800 Rambus 256MB ECC
$132.00
80 gig hard drives are less than $2 per gig. The cheapest RAM is at least 50 times that expensive. Look at Price Watch and see for yourself.
Q:How many libertarians does it take to stop a Panzer division? A:None. Obviously market forces will take care of it.
Okay, rough (dabs.com) UK prices follow...
256MBytes PC2100 DDR etc etc: £27.50
27.50 / 256 = about 10p per MByte
Seagate Barracuda 80GBytes: £164.50
164.50 / (80 * 1024) = 0.2p per MByte
So Cliff is wrong, it appears.
"I never quite thought I'd see this in my life
time, but RAM is now cheaper when it comes to
memory-per-unitofcurrency than hard drives."
On which planet is this? I walked into Fry's the other day and saw 80GB drives for $150. Show me where I can get even a tenth of that in RAM for the same price.
Just incase you didn't know. Take a look before you post, just peruse it. I mean how man posts of "What happens if the power goes out" can one have? I mean really?
"I never quite thought I'd see this in my life time, but RAM is now cheaper when it comes to memory-per-unitofcurrency than hard drives."
Even using the cheapest RAM I could find and the most expensive HD I could find, you're still off by factor of 4:
PC100/64M = $3 -> 21.3M/$
Seagate/18.2G @ 15KRPM = $239 -> 76.2M/$
Damn. That's some sad shit when someone who thinks he's a nerd can't handle basic arithmetic.
>>>
RAM is now cheaper when it comes to memory-per-unitofcurrency than hard drives.
In general, RAM is still about a 30x more expensive per megabyte than a hard disk.
512 MB DRAM costs roughly $50. 76 GB HD costs roughly $250. That puts RAM at ~0.1 $/MB and HD at 3.3x10-3 $/MB. 76 GB of RAM would cost ~$7600.
The price per meg for a solid-state HD would be worse than straight RAM since one needs the RAM, for starters, and then a controller/interface, battery, and some non-volatile storage. If the storage is flash then the price/meg just went way up. If a HD then, well, duh.
Now if there's a big break-through in inherently non-volatile memory, like dirt-cheap FRAM, then we might have something.
-Iz-
Instead of a solid state drive... I think what would be more useful might be a new PCI ATA100 controller card with a dimm slot or 4 for a nice, fast buffer. I know some SCSI/RAID controllers have been putting large caches on their cards for a while... I wonder if this idea could be applied to an ATA controller for a beneficial effect using cheap, readily available PC100, PC133, DDR, etc dimms.
Wait, you're missing something. This is slashdot! Just saying something makes it true! Watch this:
This comment should be modded up.
I can't spell or type, but that doesn't mean I'm unusually stupid.
No offense, but could an editor please fix this? I'm almost embarrased to say I frequent the site at this point.
Yes, RAM is cheap, but unless you regularly swipe sticks of it from factories in Asia, its *not* cheaper in memory-per-unit-of-currency.
Sometimes I wonder if the /. editors even frequent Pricewatch like the rest of us. Here's an example:
$3 for 64 meg is the cheapest memory-per-unit-of-currency on RAM
That's 64 meg/3$ = 21.333 meg for a buck. Remember this is the *best* memory/currency ratio for RAM on Pricewatch. (And thus the world)
$199 for 25.0 gig is the most costly memory-per-unit-of-currency on Hard Drives. /$199 = 125 meg for a buck. Remember this is the *worst* memory/currency ratio for HDs on Pricewatch (And quite possible, with *that* high of a cost for a measly 25 gigs, the world. Do *not* take up that deal.)
That's 25,0000 meg
So yes, at this point I'm embarrased to see that above comment by the editor.