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Money will buy a fine dog, but only kindness will make him wag his tail
RAM disk returns but cost still a burden
FLASH-BASED SSD storage is the next 'in' thing for the 2008, from high-end " enthusiast" PCs, workstations and quick-boot server nodes to high-fashion notebook supermodels. The latter have much in common with some of the real world supermodels - thinness, cost and, sometimes, intelligence.
The new drives' cost is still the key bottleneck in widespread adoption, aside from awaiting the standardised ONFI flash storage all over the place in a years' time. Even then, in many cases, the SSD drives will still be the 'primary' storage for the OS, major apps and speed-critical data, with all the rest on the good old hard disk.
What about making use of the recent massive price drops in the mainstream DDR2 memory? After all, it is tested, proven on both speed and read/write reliability, and will be around with us for a long time, even after Intel switches mostly to DDR3 by the end of 2008. And, if you migrate to a DDR3-based system by then, there should still be some use for that DDR2 memory.
Since 8 GB of good DDR2-800 memory can be had for as little as US$ 200 these days, and its speed vastly exceeds that of flash in any incarnation, how about creating a simple card using all the PCI-E x16 based wide-bandwidth (2 x 4 GB/s for PCI-E v1, or 2 x 8 GB/s for PCI-E v2) with four-DIMM dual-channel sockets for that spare RAM, plus some battery backup to keep the contents?
Gigabyte did offer a PCI-E based solution like this, but it only used PCI-E x1 width, nullifying the DRAM's wide-bandwidth advantage. So, the knowledge what to do is there - what to do to bring it to the next level?
Just one word - the controller. A simple, efficient and inexpensive dual-channel DDR2 controller with PCI-E x16 interface to the host PC, in a way a half of a typical chipset North Bridge, which can take care of a bit of overhead in mapping that memory as a storage device.
The cost? If produced in any volumes above a million, we'd be talking about at most $60 for the card itself including the controller, four DIMM sockets and the necessary battery backup. Then, just add the DIMMs - the cost can vary from $200 or less for the current 4 pieces of 2GB DIMMs, to zero if you're just moving over the modules from your just-retired PC.
The gains? even with just 4GB, it is still enough to at least load the OS - OK, XP only, not Vista - in basically a second, or use it for the critical working file sets during the system operation - if 8GB is there, you could manage the OS and main apps loaded in that same time. With a good controller alike those in FB DIMMs allowing simultaneous reads and writes over the PCI-E v2, I'd expect something like net file bandwidth of around 3 - 4 GB/s maximum per direction, and access time of way less than a microsecond. Not bad compared to the fastest 15K rpm SAS or SCSI drives at 100 MB/s bandwidth and some five milliseconds latency.
Also, not bad compared even to next generation ONFI v2 flash drives where even the most expensive four-channel ONFI DIMM won't be able to break 500 MB/s bandwidth in early 2009.
The real gains? Well, besides truly instant OS and critical apps & data load and save, supported by the background saves to the main storage device, you'll spin you hard disk less, and make use of the mostly wasted spare second PCI-E x16 slot which 99% of users do not use for the overhyped SLI and Crossfire. Plus, since even DDR2-667 in two channels would saturate the bus, you don't need to overclock these DIMMs at all - they can run at the cool standard speed and standard voltage, without adding much extra heat into the system.
Ever thought of 32-bit Windoze high end games or other apps who run out of memory and start swapping? well, this is one way to keep them running at high speed without having to wait for the 64-bit versions.
The dangers? Well, that battery better not fail... and, frankly, if there is a spare few dollars, I'd prefer ECC DIMMs. If these are too expensive, there is always the "custom" alternative - allow the controller to create a kind of Memory RAID-5 using standard cheap non-ECC DIMMs.
That means, you buy 5 or 6 pieces, not 4, and the spare DIMM pieces can then provide the RAID5-like error check through the controller of course. All we need - in absence of just modifying one of common mainstream chipset North Bridges for the purpose - is a good controller ASIC to matchmake this spare RAM to the rest of the system over that rarely-used spare PCI-E x16 slot. Any takers? µ
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I would be a taker for that idea. Just add an external plug for power along with the onboard battery and I would feel better. You could plug the external power to a UPS for even more redundancy.

Would be nice if you could manage 16GB on it though. There would be alot more variety of uses available at that point after getting the OS on there.
Correct me if I'm wrong, but haven't you just described a zero channel raid controller with some onboard DDR2 cache slots?

However, having just gone to look for such a device, I find there is indeed a lack... Surprising to me as I remember sticking old SDRAM sticks into an IDE raid controller many years ago.
Why not give it an SATA interface instead, through the memory controller?
I'm all for something like this, and don't care so much if it works for Vista or not. 8GB with the instant throughput we are talking about would be amazing. I'm all for paying even $500 to get this kind of thing.
Then you'd be limited to 300MBps, instead of the 4GBps of pci-e 16x v2.
With 2+ gigs of RAM, XP becomes pretty responsible (unless you bloat it with ad/spyware for good). In fact, most users won't be able to match its speed on a decent dual-core system anyway.

So, if you are not a Photoshop/3D Studio freak - why wasting that precious RAM drive on the OS when you could fire your favorite games for no time from there (with no concerns about the ECC lack)?

Ofc. you will always need more than 8 gigs and will have to limit to 2-3 recent games tops, but many gamers keep few titles at a time anyway...
An even better option... Offer a full-length card with 16 slots. Offer the product in both DDR and DDR2 options.

I have about 20 Gigs of DDR sitting around, in 512 sticks. That'd be a nice free way to utilize the old cards. DDR2 I'd have to go buy.

Also, wouldn't be a bad idea to sell daughter cards that plug into PCI or PCI 1x slots for power only, to expand even further.

This would allow those with more dollars than sense to build a reasonable 64 GB or so RAM drive.
You mean like this?

http://www.cenatek.com/images/img_rocketdrive_large.jpg

SDRAM-based solid state storage systems have been around for several years. Unfortunately they've been very expensive @ $1000+.

What would be even better is if something like this was built right onto the motherboard. A bank for "RAM" and a bank for DDR-based "SSD". The SSD portion would be battery backed, with an option to dump it (bitwise differential) to harddrive at shutdown so in the event of complete power loss, the SSD bank can be reloaded.

Or some such nonsense...
Gigabyte's car sits in the PCI slot, but it is actually connected to the storage controller via S-ATA, so there is no OS issues with drivers.
Anyone??? I'm ready to invest in this one!!!
SATA bandwith is 3Gb/s while with PCI-E you can get 3GB/s YES GB not Gb.
I always think to myself why they put those damn SATA connectors on these drives... are they dumb??
Here's a product that uses DDR in a 5.25"-sized enclosure connected via PATA or SATA:

http://www.hyperdrive4.com/
If you underclock the memory as far as possible in low power states how much power can it realistically use?

A half decent lithium ion should be able to maintain even 8GB of DDR2 for a good long time once everything is underclocked and in 'stand-by' mode.
This sound like a GIGABYTE GC-RAMDISK except it uses DDR instead. It can be loaded with 4GB of Ram.

http://www.gigabyte-usa.com/Products/Storage/Default.aspx

Here is same review about it.

http://www.hexus.net/content/item.php?item=6200

http://www.hothardware.com/Articles/Gigabyte_IRAM_Storage_Device1/

Hope they built it with DDR2 instead.
I want a Flash drive, but I don't want to pay much for the memory. Why not create a RAID array that I can plug USB thumb drives into? Give me a way to plug-in 64 USB drives, and I'll finally have a use for all those low-capacity flash drives.
RU Sure about the Gigabyte device? Gigabyte's iRAM (which I have three of) was PCI. However, it only used PCI to charge the onboard backup battery. It was actually SATA150 and could run up to 4GB of DDR RAM. The iRAM2, which was bay-based, never made it out the gates.
It would be fine to use it for the OS. Just set it to back up to hard drive just in case of a power failure. perhaps at shutdown, or intermittently throughout the day while the system is idle. Keep as many backups as you like, or use it to boot different OS images at will. With enough speed you could literally load your own OS at startup instead of using different user accounts.

If the controller setup didn't make it look like a hard drive, you could just use it as a RAM extender for boards with too few memory slots. Perhaps etch it dual function on die to increase sales and usefulness. How much extra silicon could it possibly take?

Interesting thoughts and a good read all around. Way to go Inquirer. Sets my mind to thinking. 

Hmmm... This isn't patented yet? Maybe you guys should protect the idea some how? Creative Commons or some such? I'd hate to see some single company monopolize the idea.
You can get one from http://www.hyperossystems.co.uk/ called the Hyperdrive4. Unfortunately they have decided to charge $2390 for a model that will support up to 16GB of Ram. Had that been $100 or so, I'd have bought a couple.
Yours,

Alan
If your running linux you can already use some of your video ram as a very fast swap file. I'm using 124MB of my 256MB as a swap right now.
As an owner of a Gigabyte I-RAM, I am very pleased with the performance. I've outfitted mine with 4GB of DDR400. Great performance gains on Photoshop and a great deal of other apps. I use it mainly as a page file and scratch file for PS.

More vendors should get into this market. DDR2 is cheap and 8-16GB would be great! Awesome way to give 32bit O/S's a nice boost.
Hyperos have been producing such a device for years, along with battery back up and multi-boot options for software installation and back up. Last time I looked they were up to 16 GB drives, but weren't exactly cheap.
You should add drive redundincy to this. Shadow everything within this PCI-E RAM Drive onto the hard drive. On boot it will check the card, if the OS is there it will bot from that, if not it will then load from hard drive to card and Main RAM simutaneously. This may cause a slower boot at times but the speed increase on other boots would be dramatic. What about even just doign this and setting up like a 4-8 GB pagefile?
DDR2 SODIMMS are very cheap at the moment, you could get 8 in less space than you could get 4x dimm slots in. Even better you could put them on both sides of the card for 16x dimms. 

Coupled with 2GB modules then you're looking at 32GB which is enough for vista and a few apps.

Just keep building on the idea until it's perfect and then get someone to build the thing.

Oh and don't limit the support to 2GB sodimms we would like to see 16 x 8gb sodimms. Might never see it on DDR2 but we might see 4GB on DDR2.

Some sound ideas though. iRAM showed the way. Time to exploit the idea's potential.
ahh iram v.dukenukem

just get hackintosj friendly dual quad...mount tmpfs and you have ramdisk, transfer data from dvd-rw or chainload from a usb chip.
lots of boards will support 16 gb, 1 gig for each core and 8gb ramdrive sounds good to me.
gig net will limit you to around 50/mb/s
the idea is to have good scratchpad, mount isos and run right from ramdrive, esp is db and web server apps and caching.
alternatively you could buy 4 gOS dev boards with 2 gig each and have a 4 gig ramdrive though it would be more virtual and on the network. commodity 10g network parts can't come fast enough.
the gOS cluster will use much less power and have built in redundancy. soho/smb secure enterprise botnet? the users use diskless thinclient iso from cd and power the cluster through their searches and collab via intranet app server. blades are somewhat like this but basement supercomputing may come upstairs and join the 9 to 5 cubicle crowd...meanwhile in the background a data tsunami is being tamed and made to work more efficiently.
add another box to scale is sensible.
Let's make it a programable HDD that has a huge cache of volitile memory with a battery backup. Have an erased and active state. At shutdown, write the cache to the HDD with an equal size partition and keep the cache alive on battery until the pc reboots. If the battery dies, refresh the cache from HDD. If the battery is still active, then the contents are ready for read from cache during boot. Best of all worlds - fast, not limited to so few read/write cycles, and non-volitile as a system working together.
Since when did Gigabyte release anything for PCI-e? Oh yeah, some lousy demo at some tech show. They haven't released anything since then. Even the PCI-e version would be nice over what is currently available: a DDR1 SATA RAMdisk that uses the PCI slot as power.

What I don't understand is why nobody has capitalized on this and pushed their sad implementation out of the market--however small that is.
You don't actually need ECC RAM to do ECC on something like this. You can just design the controller so that every ninth byte is an ECC byte. That means what you only get 7.1GB out of your 8GB, but it's better than no ECC.
Remember the old RamDrives? I still think adding the same DDRs to main memory (battery backup can be added) and having either the MCH or the OS be smart enough to manage the extra memory is the better option. Why bother with the extra PCIe hub, card and such when the memory can simply be hooked in the MCH?
The OS should make smarter use of the memory available if given 4Gb+
would the small amount of power a Power supply constantly feeds in it's soft off state be enough to feed a few memory chips?
http://www.tgdaily.com/content/view/34065/135/

That would be good enough for me!
michael K is correct: the Gigabyte product pluged into old PCI slot for POWER and connected datapath to PC using SATA.

they then made V2 with a 5 1/4" bay that got power from molex if i remember (a step backwards).
the real stupidity was limiting the datapath using sata 150mb/s speed, as the controller on the card was an FPGA so they could easily have provided firmware upgrades, or made new product with SATA 300mb/s.
even DDR saturated SATA 150mb/s with oodles to spare :)
Correct me if I'm wrong, but aside from improved boot speed, you'd theoretically get the same performance benefit from buying 8gb RAM and having Windows use the free memory as a disk cache (which it theoretically does automatically).

Unfortunately Windows also flushes at least a few bytes to disk literally every second, preventing it from spinning down when "inactive." :(
The main problem with using a DRAM-based ramdisk is that if you cut the power, the data on the drive evaporates after just 2 days.

Check out FusionIO. They chose to build their SSD card based on NAND flash (so it doesn't depend on battery or AC power) 

They solved the speed issues of NAND by using multiple (160?) concurrent channels:

www.fusionio.com

And I've been looking into developing such a product myself for a while, though it seems more difficult than soldering a DDR controller to a SATA controller, and I have no background in making chips yet. :-(
Lattice makes some nice FPGAs for the job. Ones from Altera and Xilinx should be okay too.

The HDL could be GPLed too.
Ok, I might need to brush up on my hardware knowledge, but how exactly would you boot from this RAM disk via custom ASIC controller without BIOS support (which I presume does not exists in any current MoBos)
This kind of thing would only be rly useful 4 professional appz like AfterEffects, Premiere, etc. But u would need a lot more space for those appz and content. Final Cut Studio 2 almost takes 65GB... I prefer Raid 0 w/ controller card and a pair of 150GB WD Raptors. OS X boots up in 3.2 - windows in 4.3 secs... 

I remember an ISA card that had some dimm slots on it. Had one on my k6-2, had four slots for pc100 each supporting a blistering 32mb of ram!!! I'd be all for this idea. Since 8gb of flash is getting cheap you should adding somthing like to as a back up. I'd buy one then.
old story! Did that already 1997 with Win 3.1 and later with Win95 but at that time no company was interested in Fremont!!
For now on XP run a Ramdisk and move all your cache and pagefile in it :-)
Add an automatically mirror on a hdd partition (RAID 1) and a software/driver option to create virtual ramdisks on it. Like having a partition for OS and another partition for data. The data partition could have a game installed or some big application which you can switch to only by loading the image(saved on the old hdd). Something like when you run your game it automatically loads the right ramdisk image and everything goes faster (or load the image manually).

On another note, 16 GB or more would be nice - or the ability to run 2 of this in a SLI/RAID-0 mode(motherboards with 2+ 16x PciE slots). The controller would be a PITA to program and debug.
Actually I don't think your RAID idea will work, at least not without tweaking your controller setup to spit out error-checking codes like a disk controller does, and thereby chewing into the capacity hard. The problem with RAID is that it's dependent on existing drive features like that to identify the bad drive or data and without those features it's impossible to find out which data set needs to be recalculated.
"Gigabyte's car sits in the PCI slot, but it is actually connected to the storage controller via S-ATA, so there is no OS issues with drivers."

I think that the Gigabyte SATA-based PCI-card could be used in a dual setup so that the MB SATA RAID 0/1 controller would use these two RAM cards as it would do with two SATA HDDs. I think I am mostly happy with boot speeds (not that important), but would use the drive for Windows, Photoshop, 3DS etc. swap files. Those can not be configured to use RAM only even the systems has lots of RAM free. But using the RAM as swap would speed up the system enormously. Still a PCIe-16x solution would be better (and a real fine use for a x38 board...). Especially printing (plotting) >2 GB files is pain, but a 8 GB / 16 GB RAM drive would change things pretty much.
I find that SSD flash drives should be for laptops, high capacity ram drives and Hard disk drive combos on a desktop would be ideal and remain a good reason to buy desktops. Wide commercialization of affordable high capacity ECC ram drives actually is a good opportunity for ram companies.

Gigabyte had great promise when it announced sata2 8 GIG DDR2 capacity and i dont know who and what pressured 
them into hindering the progress of their ramdrive.

Anyways, i to , fully support the progress of low cost high capacity (DDR2/DDR3 dual compability) ramdrives/controlers for the desktop.
Looks good, what about adding a couple of USB slots for some memory sticks that could be used to backup the main memory just before the battery runs out. Vista allows for a similar trick with the hard drive in hibernate mode. 

I could finally use my 680i’s third PCI Express slot to be used.
It really is confusing why these haven't been made already. I tried looking for one of these about a year ago as it seemed like a common sense thing for a company in this market to capitalise on. If anyone in the industry wants to let us know why...
copyright the idea my man! good thinking ;) just don't forget us poor folk when ur minted - muhahaha
I've thought of this exact idea for a while now, Gigabytes was good in theory, but is only DDR1, it needs to keep up with the market for latest price/performance RAM. 

The battery would be the only issue really, I guess you could make use of standby mode?
dont aim so low... take over a whole 5 1/2" bay and toss a cable down to PCI-E add a battery indicator light (eg, green/orange changing LED) with speaker warning, and if you use both sides of the PCB (one for chips, other for slots) you might be able to fit 8/10 slots. allowing a max of 20Gb...

the main problem with Gigabyte's Iram was its silly use of PCI for power... and using Sata 1.
maybe they would re-visit it for us geeks?

add in some software emulation to inteligently swap files (eg, on shut down load OS into ramdisk for boot, on loading a game load its files to disk, etc) and we'd have an incredibly powerful multi purpose disk.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=290179844970&ssPageName=STRK:MEWA:IT&ih=019
The RAM used would have their reliability & durability in question. Anyone has RAM faild before? Its not pleasant at all if it has your OS & other main apps in it.
Just use a RAID-0 array (software / onboard pseudo-hardware) of flash-based SSD drives (32GB are "cheap" now). Access times and bandwidth should scale linearly until whatever interface is used for the controller is the limit and the capacity would be more reasonable than with a RAM-based solution (which would also require more power). 4 x 32GB IDE flash drives would cost about 1200-1500 EUR including controller (less than half the cost per GB compared to a RAM-based solution) and give you > 200MB/s read, 120MB/s write speed and fast random access. Soon you will be able to buy 64GB SATA based SSDs and it'll be no big deal to put 8 of them in a desktop system for 500GB of storage and 480MB/s sequential read speed (at current prices, that'll still cost you EUR 8000 though).



The article describes a component that is already available. Check out the 'hyperdrive' available at
http://www.hyperossystems.co.uk/
The only downside? It will cost you $2400 US for a 16GB version and $3000US for the 32GB version. I've been hoping some company would come out with some competition to drive the cost down. It's a shame the folks at the Inq can't use thier contacts with the major firms to get it done.
I do like the idea, I've been thinking along the same lines for a while.

But, I think that the price estimate is too low. Twice the price would likely be closer. The custom controller would hike it up.
SATA is too slow, same with all the existing PCI controllers like Gigabyte's and Rocketdrive. I don't even know why they bothered with standard PCI ram drives, by the time ram was cheap enough to use them hard drives were already in the 60+ mB/sec range, not worth paying big $$$$ for a few gigabytes of ram going 133mB/sec over PCI.

I'm really looking forward to 16x PCI-E ram drives, wonder what's taking them so long? I'd love to put some of that old DDR ram to use that doesn't work with all the new DDR2 boards.
I've been looking into solutions like this on and off throughout the year.

Best I've seen has been the increasingly hard to find Gigabyte i-ram, which does draw power from the PCI bus and interface over SATA. But with huge latency advantages seems to perform well still. They've produced another version recently, with the same specs, which sits in a 5.25" bay.

I'd really love a new version which used DDR2 (cheaper than DDR1 these days), 8 or 16GB support, and either SATA2 or PCI Express. Though when I emailed them to enquire, they couldn't confirm any plans to produce a new version.

Ideally both solutions would be great:

- PCI-E for uberfast RAM cache
- As many as you can fit in 5.25" modules over SATA2, as a secondary slower RAM cache
There are devices that do this today in a 3.5" form factor - aka.. http://www.tigicorp.com - the only company I have found with the form factor, design and Intellectual Property to do this and still maintain low power. Since reduced power consumption also means you can add more ram, disk, processor, whatever in the same chassis or data center - it makes this solution even better. Faster devices sometimes mean less devices, thus less power.

In regards to TiGi, a single device has the ability to saturate a 200 MB/sec or 400MB/sec Fiber Channel Interface and can be picked up for relatively low cost versus buying equivalent speed technology in NAND / Flash / or traditional disk technologies. BTW, DRAM SSD's also have a high MTBF versus alternatives and no predicted failures based on # of reads / writes. As I understand it, the DRÅM SSD product has the capability to move 2.5GB/sec today and 6GB/sec with a future processor change (the later providing at least 1,600,000 IOPS). With a Fiber Channel interface today and the ability to add SAS, SATA, other easily - its a terrific design.

The battery really isn't an issue since it's only used to store the data to a microdrive in the event of a power loss. NAND / Flash isn't necessarily bad - it just depends on the use case and the data storage itself fails after limited use versus a battery.

So which technologies can take advantage of this? PCI Express for one and Infininband as another. The later being preferred.
Your description of the Gigabyte I-RAM is brutally incorrect.
Why overcomplicate matters?

SuperSpeed Software has been making RAMdisk software for 20 years, and 7 different OS's 

www.superspeed.com 

To be fair, I work for SuperSpeed, so maybe I am biased.. But customers can make up their own mind 

NPS
We are ready to give a try to a dozen of such cards running on Win2003 x64 servers, in order to use this RAM drive for the log file of SQL servers requiring ACID.
I've been tempted to try getting a mobo that supports 8GB+ of DDR2 onboard video a cheap cpu and w/ 1000Mbps lan connection then taking most of the ram except maybe 256-512mb of it for the OS/Video card to use as a ram drive to be used for file sharing over a local area network, but I'm I dunno if the lan speed/bandwidth would be quick enough for it to be worthwhile trying. If I had a second computer I'd just test it out with a smaller ram drive between them.
I'm in too.

The SATA interface is the Gigabyte i-RAM solution. It is an unnecessary bottleneck for performance.

I'd prefer to have an flash memory on it to save data in case of power loss. Note that 8GB save to flash lasts 7 minutes (assumed write speed 20MB/s), so battery can be small.

Northbridges typically (i.e. not server chipsets) only support 4 DIMM modules, so today cheap 8GB modules are easy to build, and soon prices for larger modules may fall. Intel's 5100 MCH could handle more DIMM modules (up to 48GB) with registered ECC RAM which is currently available at nearly the same price as non registered non ECC RAM. But probably the 5100 is too expensive.
There is an old VIA chipset P4X400 with 8 DIMM modules, but only AGP 8x, no PCI-x. 

There are Northbridges with integrated processors (VIA, old Geode, Transmeta). Maybe this could be interesting.

The other alternative is having more RAM on the motherboard, a RAM disk with suspend to somewhere in case of power failure.

Finally one could simply link several PCs (or motherboards) having their own memories, in a cluster.
hey i can build it i need a few grand to create a production model but once i work out the basics hek how bout a 512 bank model parallel gigbit interfaces over cheap cat5. this is why i hate the commercial crap no real performance until you multiply the price by 100