If somebody asked me at this time last year if there is such a thing as fast DDR2, I probably would have laughed in their face. Not so much anymore. Why the change now? As we've seen throughout the year, speeds have been increasing and latencies have been lowering.

Motherboard chipsets have also become much more sophisticated, and as we've seen with the nForce 4 SLI Intel Edition, there's a strong case for DDR2 now. While DDR2 has been something of a hard sell for many users, it has steadily, albeit slowly, gaining acceptance among enthusiasts. With AMD slated to possibly offer DDR2 with their next-gen platform, things are looking up for the oft maligned ram format. It also helps that dual core processors can do more to saturate the memory bus than their single cored brothers.

Today we'll be checking out kit. These modules are based on the XMS2 line, and feature black coloured heat spreaders.

Specifications

Part Number	Speed	Size	Package	CAS Latency
	XMS2-8000UL	1GB	2x240 DIMM	5-4-4-9-T1

You can view the full specifications in this , but what you need to know is the modules are validated with multiple Intel based motherboards at 1000MHz. Yes, those are three zeros at the end.

The two ram modules, each weighing in at 512MB, arrived in a hard plastic case, with each ram module fitted in the clear plastic shell. It's worth pointing this out is because there should be no confusion in what you're getting. You have a clear view of the ram, and the labels (indicating the type of modules), and the packaging is snap sealed. The seal changes to a slightly translucent white when opened, so it should be pretty obvious to the buyer if the package has been tampered with.

As previously mentioned, the modules have black coloured heat spreaders. Along with improving the cooling of the ram, the spreaders (from what I was also told by a marketing rep) will reduce EMI since it shields the ram, but I don't have any quantitative proof of that.

The kit is rated at PC2-8000, which works out to 1000MHz, or a cool 1GHz. The ram timings are quite low, 5-4-4-9 at 2.2v, and as many enthusiasts know, tighter timings normally result in better performance. Still a far cry from the 2-2-2-5 we're used to seeing from lower speed DDR, but as memory speeds increase, it is extremely difficult to maintain stability with such low timings. Lately we've noticed that the timings seem to be having a lesser effect on performance as memory speeds increase.

All of the TWIN2X kits are tested in pairs and in a Dual Channel environment, which all of Intel's new chipsets (including offerings from VIA, NVIDIA and ATI) support. Pictured above is our test environment which includes an Intel Pentium Extreme Edition 840 and MSI P4N Diamond nForce 4 SLI.

Overclocking (or underclocking?)

A will be used to test for reliability as well as stability during our overclocking tests. The card is quite expensive, but if you're testing a lot of ram, or you're a technician troubleshooting systems, this card is well worth the money.

How it works is that the R.S.T. Pro2 goes into a free PCI slot and after POST, it bypasses the OS completely, loading a proprietary OS and software package (embedded on the card itself). The card allows you to perform stress and performance benchmarks without the Operating System's memory footprint, memory resident programs, or drivers interfering with the memory installed.

Before continuing, first a disclaimer, your mileage may vary. The MSI P4N Diamond is a great overclocker, but according to the BIOS, 900MHz was the ceiling of this board. Basically, there's no way to even hit the maximum supported speed of this kit. We'll see what we can do, but this is the information we had before we even started.

By default, the ram was configured to 667MHz upon installation. We had to set things to manual in the BIOS to change these settings, and after doing so, we managed to hit 720 (despite setting it to 725, it dropped to 720 once we hit Enter). At this point, we began to experience problems. We raised the voltage slightly and the problems went away.

Next stop was 800MHz. This was no problem provided we boost the voltage to the Corsair supported max of 2.2v. We continued upwards and got as high as 900MHz, the board's maximum.

For the heck of it, I went for 1000MHz, which the board allowed us to enter. I kinda figured it just displayed that, but was really running at 900MHz. We rebooted and were greeted with no POST. We rebooted the BIOS several times to no avail.

Before firing off angry emails to Corsair and MSI, I removed one of the sticks and rebooted. The system restarted and POSTed. The BIOS reported the ram running at 667MHz (this was expected since we reset it), so I figured we killed a stick. To be sure, we swapped modules and behold, that one was working as well. We boosted the ram to 800MHz, and no problems at all.

We then tried both sticks in the other ram slot and the system would not boot. For kicks, we placed a ram module into the working slot, reset the BIOS again, then placed the second stick in the non-working slot and did another reset. Power was turned on and the system booted up with both channels working. To make a long story short, MSI's safety measure seems to be it deactivates a channel during a bad OC and our totally nonscientific method of avoiding a RMA return worked out.

Oh, lest we forget, at 2.2v, the maximum stable overclock (passing the R.S.T. Pro2's tests) was 930MHz. We did get as high as 940MHz, and the system did run, still passing in the R.S.T. Pro2 test, but would lock up whenever we fired up a benchmark.

Test Setup

MSI P4N Diamond nForce 4 SLI: Pentium 4 840 Extreme Edition, 2 x 512MB Corsair TWIN2X-8000UL, 2 x MSI NX7800GTX, 160GB Seagate SATA 7200rpm, Windows XP SP1.

The comparison memory will be Crucial's Ballistix 6400 (800MHz), and Corsair's XMS2-5400UL (675MHz), both 1GB kits, running at their default speeds and timings. The Corsair TWIN2X-8000UL will be run at both 800MHz and 930MHz at 5-4-4-9.

SiSoft Sandra 2005 Memory

Just a reminder that the MSI's FSB increased past 200 once we passed 800MHz memory, so the overclocked (for the motherboard) scores will not be "true" memory benchmarks in some cases. That being said, we can see that the overclocked settings run away from the rest, but at 800MHz, the slightly better timings (despite having a higher CAS setting) on the Corsair keeps it slightly ahead of the Crucial. These results are synthetic though, so let's look at real-world scenarios.

Battlefield 2

Looks like the trends seen in SiSoft Sandra is continuing here. Naturally, the 930MHz settings help the most, but at 800MHz, the Corsair 8000UL still stays on top of Crucial's kit which is running at the same speed.

Unreal Tournament 2004

Another close finish between the Corsair and Crucial kits, but again the 8000UL finishes on top. We haven't talked much about the 5400UL, but given the differences in clock speed, it's last place finish is to be expected. What is surprising though is it does stay close thanks to it's more aggressive default timings.