by Ilya Gavrichenkov
08/08/2004 | 11:38 AM
The popular U.S. manufacturer of overclocker memory modules, OCZ Technology, keeps on expanding its product range. Yes, non-standard top-quality high-performance memory is still the company’s main priority, but now the PC enthusiasts are served other products as well. Among them are coolers and heatsinks, power-supply units, cables, thermal compounds and what not.
Recently, OCZ Technology added another most fascinating gadget to its assortment: OCZ DDR Booster Diagnostics Device. This accessory is not a memory module proper, but has an immediate relation to PC memory. The DDR Booster is an additional power supply circuit for DDR SDRAM modules – by plugging it into an empty DIMM slot, the user gets widest opportunities in controlling the memory voltage.
We, at X-Bit Labs, have never met such devices or analogs, so we were most curious to put this Booster to test.
The OCZ DDR Booster with patent-pending PowerClean technology supplies “cleaner” power to the installed memory modules and allows increasing their voltage above the rated one. It adds stability to the system as well as increases the overclockability of the memory modules. The Booster is equipped with a two-position LED indicator showing the current voltage on the DIMM slots. The formal characteristics of the OCZ DDR Booster are as follows:
The accessories to the OCZ DDR Booster include a special power cable and a user manual with a list of all the compatible mainboards.
Of course, the appeal of the OCZ DDR Booster also depends on its pricing; right now, the device can be got for about $60.
Before testing the OCZ DDR Booster, let us try to clarify what this device is actually for. Evidently, its main purpose is in providing for higher voltages on the DIMM slots. This may really come in handy at overclocking. It is a well-established fact that the maximum frequencies of many memory modules depend heavily on the supply voltage. Mainboards that allow tweaking Vmem often do so in a limited scope – usually no more than up to 2.8-2.9v. Our experiments suggest that this may be not enough for extreme overclocking. These restrictions led to the so-called volt-modifications as the users make changes to the DIMM slot power circuitry to reach higher memory voltages. According to overclocking practice, a DIMM voltage increase to 3.2-3.3v doesn’t cause any irreversible consequences if done with proper cooling, but dramatically improves the memory’s overclockability.
Volt-modification of a mainboard, although a popular method, requires good soldering skills from the user. It also deprives you of the warranty on the mainboard. The OCZ DDR Booster helps to avoid these problems. It can easily raise the DIMM slot voltage to 3.9v without any hardware changes.
The device itself is in fact an independent power supply circuit. By installing the OCZ DDR Booster into a free memory slot, you link it to the memory bus. The device plugs into the mainboard’s own circuitry and supplies additional and pure (i.e. stable) voltage. The Booster receives power from the ATX power-supply unit directly and thus can increase the voltage of DDR DIMM slots regardless of the BIOS Setup settings as well as of the mainboard itself.
The Booster is not a complex device at all. Frankly speaking, I was rather surprised to see it selling for as much as $60. Well, you buy the idea for that money, too, and this idea is simply brilliant. So, the Booster consists of two functional units. The first unit is responsible for displaying the current voltage value on the LED indicator. The second unit is actually an additional power supply circuit for the memory bus.
The display unit is based on an ICL7107 digital-to-analog converter from Intersil. This chip features an internal circuit for displaying the voltage value on a LED indicator – thanks to that we see the current voltage of the DIMM slots. For a precise setup of the showings of the LED indicator, the OCZ DDR Booster also has a small trimming resistor. I don’t think it’s of any use for us since Boosters are calibrated back at the factory.
The power supply circuit is based on four MOSFETs, covered under copper heatsinks. A second potentiometer, easily accessed by the user, adjusts the output voltage of the circuit. The power circuit of the OCZ DDR Booster connects to the PSU through two Molex connectors. By the way, you should connect the Booster with the enclosed cable only and make sure you plug everything right – although the device carries ordinary Molex connectors, their pins have non-standard values.
Thanks to this most simple design, the Booster is compatible with a lot of mainboards; the manufacturer’s website has a long list of compatibility-tested mainboards. I won’t copy’n’paste this list – just know it is long, although not without exceptions. For example, the design of the power circuitry of such mainboards as ABIT KV8, ASUS A7N8X, DFI nForce2, EPoX 4PCA3, FIC 875Dynasty, FIC P4M-RJ300 and Shuttle AN50R was found incapable of working with the Booster. Then, take note that the Booster is bigger than a standard memory module both in height and in thickness. That’s why you may encounter mechanical problems installing the device into a DIMM slot.
You may be curious to know about the Booster’s operation with a dual-channel memory controller. You may find it strange, but the device can be plugged into any free slot whatever channel it may belong and be used to control the voltage of all the memory modules installed in the system all the same. The explanation is simple: mainboards with a dual-channel memory controller use a common power-supply circuit for all the DIMM slots. Since the OCZ DDR Booster works with the power lines of the memory bus only, the dual-channelness doesn’t hinder its operation in any way.
There’s nothing difficult to using the DDR Booster. Installing this device into a free memory slot and attaching it with the enclosed cable to the power-supply unit, the user can adjust the voltage of the DIMM slots by rotating the potentiometer’s handle. The extreme left position of the potentiometer’s handle sends to the memory slots the voltage, which is set up in the BIOS Setup program; in the extreme right position, the memory receives a voltage of 3.9v.
I should note that the power circuit of the DDR Booster is rather hot at work. Keep in mind the fact that the temperature of memory modules is proportional to their voltage squared. So if you’re using this device to reach high voltages, take care of proper cooling of the memory slots. For example, I used an additional fan to blow at the DIMM modules and the Booster.
Then, don’t forget about the maximum acceptable voltage of different memory modules. With such a powerful tool as the DDR Booster, it is easy to burn the memory out completely by setting too high a voltage. For example, OCZ Technology itself only warrants its modules to work correctly at a voltage of 3.0v and less. Practice shows, however, that a majority of available memory modules can work correctly at 3.4 volts. But of course no one will give you any warranties for such voltages!
I should also stress the fact that not all memory modules can improve their characteristics at a higher voltage. Much depends on the chips the particular module is based on. My general recommendation is that you are more likely to improve the overclockability of a memory module by increasing its voltage if the module is originally designed for high frequencies rather than for aggressive timings. So, before shopping for the DDR Booster, consider the overclockability growth of your memory modules by increasing their voltage in the normal way, i.e. in the BIOS Setup.
I carried out my tests of the OCZ DDR Booster on the following testbed:
So, I wanted to watch the dependence of the maximum memory frequency on its voltage, which will be controlled by the OCZ DDR Booster device. I clocked the memory in sync with the FSB and I was overclocking the system through increasing the FSB clock rate until the memory became unstable.
For my experiments, I took untested-yet ShikaXRAM memory modules from Shikatronics Inc. This firm has recently entered the market of overclocker memory, but already ships advanced DDR550 units (PC4400) with timings of 3-4-4-8. The rated voltage of these modules varies from 2.6 to 2.8v.
I set up 2.6v Vmem in the BIOS Setup and began to experiment. You can see the results below:
The results are curious enough. First, we see that this memory, like many other modules designed for high frequencies, is sensitive to the voltage. Its overclockability grows by more than 5MHz with every extra 0.1v. After 3.0v Vmem, however, the maximum stable frequency grows but slightly, and doesn’t even change at 3.2v. I think it is due to overheat of the memory – in order to maintain the overclockability growth, you need something more than a simple 80mm fan.
Anyway, you see that the DDR Booster can really give you extra megahertz, as the BIOS Setup of the mainboard I used could only increase the memory voltage to 2.85v.
By the way, here’s a couple of screenshots to prove that I really hit a FSB frequency of 295MHz in the synchronous mode:
The OCZ DDR Booster proved to be a simple and reliable device in my tests and yet efficient and rather tricky. It really gives you the opportunity to increase the memory voltage in a wide range without any hardware modification of the mainboard. With the OCZ DDR Booster, ordinary users – not only experienced overclockers – can enjoy extreme overclocking. Although the device is not altogether blameless (its price is rather steep and it is incompatible with several popular mainboard models), it is an excellent accessory every overclocker might enjoy using.
Finally, one warning. Although the OCZ DDR Booster can be a powerful tool in the hands of an overclocker, it is potentially dangerous if wielded carelessly. Devices like this Booster must be used with all precautions necessary lest you should damage your memory, mainboard or even processor.