Ask Dan: i-RAM alternatives?

Last modified03-Dec-2011.

I'm looking for a small but high-speed access device for small random access applications - database, image manipulation, etc.
I think the Gigabyte i-RAM fits the bill - but it uses DDR1 memory, which is expensive, and so is the card. And it's only SATA/150.
I know it's still usable, but are there any better value options that, say, use Non-ECC DDR2 ($AU34 for 1Gb of 800MHz Samsung RAM is just terribly cheap!), or maybe have a SATA/300 interface, or maybe can take more than four sticks of RAM for upgrade capacity. Or even just not use a PCI slot for power - as both of my precious PCI slots on my microATX motherboard will have to be sacrificed for the i-RAM?
I was thinking of a softwareRAM disk, because that wouldn't take up anything in terms of interface (maybe a bit of CPU to manage it) - but I haven't found one that works under Windows Server 2003 R2 Enterprise x64 Edition even after extensive digging.
The other obvious problem is that all motherboards at the moment still have only four slots unless they're exotic, and memory sticks are 2Gb max per slot, making 8Gb total RAM at best.
Veronica

Unfortunately, there's nothing but the i-RAM in this market sector.

And the i-RAM, as you say, uses old expensive RAM, and has itself stayed at almost exactly the same price since it launched more thantwo years ago.

Here in Australia, Aus PC Market stock the bare i-RAM card for $AU228.80 including delivery anywhere in the country (Australian shoppers canclick here to order it), but a card with the maximum four gigabytes of RAM on it will set you back a hefty $AU536.80 (Aussies can order that packagehere).

The price becomes much more bearable if you're retiring a computer or three that have DDR RAM in 'em already, but if you have to pay the whole $500-plus, you're spending rather more than the price of a "one terabyte" hard drive, with formatted capacity around 930 real gigabytes.

You'd think someone elsewould have made a thing like the i-RAM by now. In the card form factor, or perhaps as a 5.25 inch half height device, like a CD-ROM drive. But nobody has.

Gigabyte themselves wereshowing a 5.25-bay, 8Gb, DDR2 i-RAM more than a year ago, but they haven't brought it to production yet. There was also talk of a SATA/300 DDR2 i-RAM card, but that's is similarly vaporous so far. Thereis a 5.25 inch version of the i-RAM called the "i-RAM BOX", but it's just the SATA/150, DDR-1 card version in a different shape.

There are similar devices with SCSI interfaces, but they're always very expensive. They're for big-iron server use, where even a $20,000 swap drive is preferable to replacing the whole system because you can't put any more RAM in it.

(After this page went up, a reader pointed out theHyperOS HyperDrive4 to me. It's a 5.25-inch unit with both PATA and SATA connectors, and eight RAM slots, for 16 or 32Gb total depending on the version. There are even versions that accept a laptop drive to back up the RAM contents. And the 16Gb-max, no-laptop-drive version willonly cost you $US2390 with no RAM in it!)

There doesn't seem to be much market pressure for a better i-RAM, presumably because a more elegant solution to the small set of problems the i-RAM solves is, as you say, to just get a64-bit system witha ton of memory, boot from an ordinary hard drive, and then use a software RAM disk (likeQSoft RAMDisk, for instance) for whatever applications need warp-speed disk access.

But if you can't get a software RAM disk for the operating system you're using, and don't feel like writing one yourself, you are of course still up a certain creek without any means of propulsion.

Just getting enough RAM into a normal PC to make a large software RAM disk practicable, though, is not as much of a problem as you might think. Yes, all standard motherboards have four memory slots (or fewer, for cut-down baby-boards), buthere's a six-RAM-slot (dual!)Socket J Xeon board for under $AU800.

CPUs to suit it start from well under $300. And 12Gb of RAM to suit isonly $AU1320.

(I've got more about the weird state of the current Xeon scenehere.)

There are also Opteron options that knock the above into a cocked hat, RAM-wise;this andthis aresixteen-RAM-slot dual-Socket-F-Opteron boards that cost less than $AU650. The memory and CPUs for those boards are cheaper, too.

All of this is of course probably irrelevant if you can't find a tame coder who'll write you a RAM disk. But those RAM-slot-encrusted Opteron boards are still pretty hilarious. They needregistered ECC DDR2 RAM, which isn't as wonderfully cheap as basic DDR2, but you can still get a 2Gb module foronly $AU198 as I write this (less than twice the price of the cheapest 1Gb modules).

So for $AU1,584 you could get 16Gb, and still have half of your RAM slots free!

RAM disks of all kinds have been made largely obsolete by modern operating systems. Lots of people used RAM disks back in the distant past whenvirtual memory (the "swap file") was an exotic feature, but nowadays we have OSes with sophisticated virtual memory handling and the ability to use lots of vacant RAM, if it's available, for disk caching.

Modern database and image manipulation software tries hard to use spare RAM for this sort of thing too - though Photoshop's separate scratch disk system isn't exactly cutting edge.

If you really need a RAM disk right now, then the i-RAM's an easy way to add one to an ordinary PC, and it's plentifully fast. A fresh WinXP install will load from an i-RAM (all the way to proper system usability, not just to the desktop with lots of thrashing still going on) inabout ten seconds.

Note that if all you need is really fastseek speed from a device with i-RAM-ish capacity (about 4Gb), you can get it by using a CompactFlash card in an ATA ("IDE") adapter. The adapters were pretty unusual when I reviewed oneseven years ago, but they're all over eBay for close to nothing these days.

Any CompactFlash card will work with one of those cheap pin adapters as an ATA device. You need to be a bit more selective with your card choice if you want real speed, though, because not all CompactFlash cards supportDMA transfer modes. You also can't expect more than about half of hard disk sustained transfer performance; possibly quite a bit less, and quite terrible if you're doing lots of tiny writes.

But seek speeds for CompactFlash are around 1 millisecond, versus about 10ms for hard drives. And the sheer size of cheap CF cards today means that even though they'll only survive a limited number of write cycles, using them for heavily-written devicesisn't a bad idea any more.

You could speed things up by making a RAID array of CompactFlash cards, but this is unreasonably difficult in Windows. Windows only allows you to make a RAID array out of CompactFlash cards that report themselves as a "fixed" disk, not a removable one. These cards are evenharder to find than the DMA-capable ones.

Mac OS and Linux let you make RAID arrays out of any crazy thing you want -thumb-drives,USB floppy drives,whatever - but Windows only lets you do it with fixed disks.

The i-RAM's seek speed beats even CompactFlash by a wide margin; it's down around 0.1ms. And software RAM disks are faster again. I write a bit more about this inthis USB flash drive review.

If you will settle for nothing less than a (slightly) faster, (significantly) cheaper i-RAM, Gigabyte or someone else may actually release one at some point.

But I wouldn't hold my breath.