Gigabyte i-RAM

Introduction:

Every once in a while, something cool appears out of nowhere and it never fails to amaze us the kind of ideas that are actually floating out there. The idea of using solid state memory as a hard disk drive is not new, but no mainstream vendor actually made the effort to turn it into a product. While there are actually Flash based hard disk drives available in the market today, from memory vendors like Transcend, these Flash based devices are not as responsive as we would like them to be. Although solid state memory do provide users with a really robust storage subsystem, it's seldom adopted since volatile and non-volatile solid-state memory devices are always too costly. Compare that with a typical 3.5-inch hard disk drive today and you'll see that you're actually paying about 100 times more per GB of storage for solid state memory.

Gigabyte's i-RAM storage card is no doubt one of the more innovative products that we've seen in months. We first previewed the card during Computex Taipei 2005 and it showed great promise. Although the card supports only four DIMM slots, it has the potential to house up to 4GB of DDR400 memory - enough to store an entire installation of Windows XP with enough space for a couple more applications. The card's concept is simple, use standard memory modules available today to build a so-called RAM disk. At first glance, the card does remind us a little of memory cards used in high-end server systems. On closer inspection, you'll see that it has a single SATA port which lets you connect to any SATA ports found in most motherboards today.

On the card itself, you'll find a Li-ion rechargeable battery which keeps the memory powered if one accidentally switches off the mains to the PC. According to Gigabyte, the battery can keep the data in the DDR modules for up to 16 hours. Even when the PC is shut down, as long as the PC's power supply is turned on, the standby current on the PCI bus will continue to power the memory modules - thus, the battery won't kick in only until there's absolutely no power going to the PC.

The card is not based on any common chipset and it utilizes a Xilinx Spartan-3 FPGA (Field Programmable Grid Array) chip as the main memory controller. This means that the board's controller is solely customized by Gigabyte's research engineers. The memory controller is connected to a JMicron JM20330 Serial ATA single-chip controller.

The JM20330 chip is actually a PATA to SATA bridge and this indicates to us that the board is likely not fully SATA native. Thus, it really depends a lot on the throughput rate from the memory controller although it could theoretically max out at Ultra DMA-150 (which the JM20330 could support). There's really nothing wrong with such a design concept although we know a lot of users would hate to see a PATA-to-SATA bridge in a product that is designed for high speed access. We'll leave our judgement later until we see the results in the following pages.