Case Studies

INTEL 2.6CGHZ PENTIUM 4 & AOPEN AX4SG MAX
reviously, weve examined two processors running with a 400MHz frontside bus and a few running at 533MHz. Now were ready to begin working with an 800MHz FSB. Well start with Intels 2.6CGHz Pentium 4. Intels 2.6CGHz Pentium 4 isnt much different from the 2.66GHz CPU we reviewed previously. The 2.66GHz processor, however, runs on a 533MHz FSB. Aside from supporting a faster bus speed, the 2.6C features the same Northwood core found in the 2.66GHz P4. That means its sporting the same
USB 2.0 ports, and various other I/O devices. The ICH5R adds support for RAID 0 (stripping) and RAID 1 (mirroring) to the ICH5. Using RAID 0 helps improve disk throughput by alternating reads and writes to multiple hard drives while RAID 1 protects data by mirroring the contents of one drive on another. The AX4SG Max includes two SATA ports, so youll need two hard drives to take advantage of RAID. The AX4SG includes support for dual channel DDR SDRAM. The four memory slots are divided into two groups of two (channel A and channel B). To take
section. We shunned the integrated video adapter for an ATI Radeon 8500. To support our 2.6CGHz P4, we installed 1GB of PC3200 DDR SDRAM. We wanted the hard drive to be as little of a bottleneck as possible, so we opted for an 80GB, 7200rpm SATA hard drive. (We resisted the temptation to use SATA RAID in this case study because it had been unavailable on past motherboards.) A Lite-On 48X/24X/48X/16X DVD/ CD-RW drive and an ALPS floppy drive rounded out our storage options. Overclocking Before we began to turn up the heat, we recorded scores for both 3DMark2001 SE and PCMark2002. Technically, the 2.6CGHz P4 is slightly slower than the 2.66GHz P4 (the 2.6CGHz runs at about 2.61GHz), but the 800MHz FSB does give the 2.6C chip the upper hand in 3DMark scores. While the 2.66GHz managed 10194, the 2.6CGHz managed a 3DMark2001 SE Increase 10480. PCMark2002 scores, however, were a different story. The 218 2.66GHz actually managed a slightly higher CPU score with a 6572 compared to 6515. The ASUS P4P8X motherboard we used to test the 2.66GHz P4, however, only supported PC2700 DDR SDRAM. The AX4SG Max supports PC3200 DDR SDRAM, letting us take full advantage of our memorys capability. The result was an 8009 scored by the 2.6C compared to 7262 for the 2.66GHz Pentium 4. HDD Scores were virtually identical with the 2.6C scoring a 1243 and the 2.66GHz P4 scoring a 1240. Next, we began seeing how far we could push the 2.6C. We started off as always by entering the BIOS Setup utility (press DELETE during the POST). Once in the Phoenix-AWARD BIOS setup utility, we used the arrow keys to select Frequency/Voltage Control and pressed ENTER. From the Frequency/Voltage Control menu, we were able to increase the FSB from 200MHz (remember, the Pentium 4 runs on a quad-pumped FSB,
Intel 2.6CGHz Pentium 4 AOpen AX4SG Max
Stock Performance Overclocked Performance Clock Speed 2.61GHz 2.81GHz Frequency 200MHz 215MHz Multiplier VCore 1.525 1.525 CPU 6515 6981

PCMark2002

Memory 8009 8921

HDD 1243 1276

3DMark 2001 SE 10480 10698
0.13-micron design and 512KB of L2 cache. Motherboard The AOpen AX4SG Max includes an 865G Springdale chipset. The 865G provides integrated 2D and 3D graphics using a portion of system memory as video memory. Dont worry, you can still use an AGP graphic card if you prefer something a little more powerful. The AX4SG Max supports AGP 8X/4X running at 0.8 volts and 1.5 volts. 3.3-volt AGP cards have been known to fry a few chipsets, but the AX4SG Max protects against 3.3-volt AGP cards, preventing damage to the system. While the 865G controls the northbridge, the ICH5R controls the southbridge. By now, you should be familiar with the ICH5 controller. The ICH5 includes support for two Ultra ATA 100 IDE channels, 2 SATA/150 ports, eight
advantage of dual channel mode, simply install two identical memory modules in the same color memory slot. The AX4SG Max supports up to 1GB memory modules, meaning it can support a total of 4GB of PC3200 DDR SDRAM. In addition to the well-known Intel chipsets, the AX4SG Max includes a RealTek AC97 ALC650 audio codec that provides 6-channel sound and the SPDIF connector on the back lets you pass highquality audio to compatible equipment. A Gigabit Ethernet controller is integrated into the motherboard as well and lets you transfer documents at 10MBps, 100MBps, or 1000MBps. Should something go wrong while youre installing your new hardware or trying to overclock, Dr. Voice II can tell you whats wrong in one of four languages. System Specifications Our test system used the same hardware weve relied on previously in this
BIOS Channel A Channel B ATX PSU Connector Northbridge (Intel 865G) Ethernet Controller Front USB Headers Southbridge (Intel ICH5R) Audio Codec SATA Connectors S/PDIF Out
so the BIOS shows an 800MHz FSB as a 200MHz FSB) to 205MHz. With the processors multiplier locked at 13X, we saw an 80MHz increase in clock speed to 2.68GHz (just slightly faster than the 2.66GHz P4 we looked at earlier). The processor had no problems with the slight increase and 3DMark scores improved to 10559. We increased the FSB once again to 210MHz, resulting in a processor clock speed of 2.73GHz. Once again, 3DMark scores showed modest improvements gaining to 10609. A slight increase to 215MHz resulted in a 2.81GHz processor and another small 3DMark improvement to 10698. We bumped the FSB up once again to 220MHz, but the system didnt seem to like the increase. Windows XP Pro froze on us before we could even start running 3DMark. When things get tough, the tough increase the voltage. Once again, we forged into the Frequency/Voltage Control menu and increased the processors core voltage

to 1.6 volts. We saved our changes and rebooted the system, but Windows refused to load (instead, the system simply rebooted). We increased the voltage to 1.7 volts and 1.8 volts as well, but both times the system rebooted before it finished loading Windows. Final Words Overall, the AOpen gave us modest returns. We were able to get the
Overclock Comparison 3DMark2001 SE
Intel 2.8CGHz Pentium 4 (800MHz FSB) Stock Performance 10605 Overclocked Performance Intel 2.6CGHz Pentium 4 (800MHz FSB) Stock Performance 10480 Overclocked Performance 10698 Intel 2.66GHz Pentium 4 (533MHz FSB) Stock Performance 10194 Overclocked Performance 10518
2.66GHz P4 running at 3.11GHz, but our 2.6C could only manage 2.81GHz. This might be due to the fact that an 800MHz FSB doesnt leave enough room to grow. As we move into the faster processors and FSB speeds, we start getting less from our motherboards and processors. Overall gains for the processor were modest. 3DMark scores showed improvements rising from a 10480 to a 10698. PCMark2002 scores also showed modest improvements. CPU scores rose from 6515 to 6981, and the HDD score rose slightly from 1243 to 1276. The Memory score saw the largest improvement, rising from 8009 to 8921. Compared to the 2.66GHz P4, however, the 2.6C still provided better overall performance. When we pushed it to 2.81GHz, the 2.6C delivered a 3DMark score 180 points higher than the 2.66GHz P4 was able to deliver at 3.11GHz. We give most of the credit to the faster frontside bus and better support for our PC3200 DDR SDRAM. Not surprisingly, however, the 2.66GHz did manage to receive a better CPU score in PCMark2002. The 7576 posted by the 2.66GHz P4 while running at 3.11GHz is roughly 600 points better than the 2.6C was able to muster at 2.81GHz. Given the extent to which PCMark2002 seems to rely on clock speed, this isnt too surprising. Other PCMark2002 scores, however, enjoyed the faster FSB. The HDD score was up from the 1249 maximum posted by the 2.66GHz to 1276. The 2.6C also managed a higher maximum Memory score and posted an 8921 compared to a 7649. Next, well keep the AOpen board but swap the 2.6C for Intels 2.8C. Then we leave Springdale behind to see what Intels 875 chipsets can do with 3GHz processors.

by Chad Denton

Case Studies
INTEL 2.8CGHZ PENTIUM 4 & AOPEN AX4SG MAX
lthough weve enjoyed playing with Intels Springdale chipsets, were looking forward to seeing what Canterwood can do with some 3GHz processors. First, however, we need to take a closer look at the 2.8CGHz Pentium 4. The 2.8CGHz runs on the same Northwood core. We were hoping to look at some chips based on Intels upcoming Prescott core, but it looks like well have to wait until later this year. Northwood is no slouch, but its starting to gray a bit on top and were anxious to move on to something new.
cards and includes protection from 3.3volt cards that can damage the chipset. In addition to the 865G on the northbridge, the AX4SG features Intels ICH5R on the southbridge. The ICH5R handles most of the system I/O and supports two ATA 100 channels, two SATA/150 ports, and eight USB 2.0 ports. The R in ICH5R stands for RAID. The ICH5R supports both RAID 0 (striping) and RAID 1 (mirroring). RAID 0 improves disk throughput by alternating reads and writes to multiple hard drives while RAID 1 provides a certain level of protection against data
System Specifications We try to change as little as possible from one case study to the next. Once again, our processor was joined by 1GB of PC3200 DDR SDRAM. Our 80GB, 7200rpm SATA drive provided top-notch performance and the ATI Radeon 8500 video card, although dated, still provides decent graphics. Rounding out our storage options are a Lite-On 48X/24X/ 48X/16X DVD/CD-RW drive and an ALPS floppy drive. A 400-watt Antec power supply powered the system. Overclocking Before we could get started with the fun part, we had to record stock 3DMark2001 SE and PCMark2002 scores. Compared to the 2.6CGHz, the 2.8CGHz got off to a fast start posting a 10605 in 3DMark (the 2.6CGHz started off at 10480). This score was significantly better than the 10230 that the 2.8GHz scored on a 533MHz FSB. PCMark2002 3DMark2001 scores were also higher. SE Increase The 2.8CGHz managed a 6992 CPU 229 score (almost 500 points better than the 2.6CGHz) and an 8511 Memory score (up from the 8009 posted by the 2.6CGHz). The HDD score once again hovered around 1200 with a 1209. Compared to the 2.8GHz on a 533MHz FSB, PCMark2002 CPU numbers were just slightly higher. The 2.8GHz managed a 6885 CPU score. The 2.8GHz actually managed slightly higher HDD scores at 1222, but the 2.8CGHz managed a much higher Memory score (the 2.8GHz managed a 7301). With our scores recorded, it was time to start upping the power. We pressed the DEL key to enter the PhoenixAWARD BIOS setup utility. Options to increase the FSB are found in the Frequency/Voltage Control section. We increased the FSB from the default 200MHz to 205MHz. This increased the 2.8CGHz to 2.89GHz and provided us with a modest 90-point increase in 3DMark scores.
Intel 2.8CGHz Pentium 4 AOpen AX4SG Max
Stock Performance Overclocked Performance Clock Speed 2.8GHz 3.01GHz Frequency 200Mhz 215MHz Multiplier VCore 1.525 1.525 CPU 6992 7542

PCMark2002

Memory 8511 8770

HDD 1209 1208

3DMark 2001 SE 10605 10834
The 2.8CGHz uses the familiar 0.13micron design and 512KB of L2 cache. The 2.8GHz speed should be a step up from our last Northwood, but with the fast 800MHz clock speeds and relatively low multipliers, we might not get as much of a boost from the 2.8CGHz as we got from its cousin, which runs on a 533MHz FSB. Motherboard We know it can get old looking at the same equipment, but the AX4SG Max we used in the last case study is a well-rounded board, and we opted to use it again here. The 865G supports 800MHz FSB speeds and includes an integrated video chip. The motherboard lacks video memory, however, so it grabs a portion of system memory provided you dont opt to use a standard AGP card instead. The system supports AGP 8X/4X. The AGP slot is compatible with 0.8-volt and 1.5-volt

loss by duplicating data from one disk on another. The motherboard includes two SATA ports, so you can use up to two drives in a RAID array. Like all other motherboards in this section, the AX4SG also includes support for dual-channel DDR SDRAM. The four memory slots are divided into two channels (channel A and channel B). To use dual-memory mode, simply insert identical memory modules into the same color memory slots. You must have an even number of memory modules to take advantage of dual-channel memory. Each slot can support modules as large as 1GB, so the motherboard can support up to 4GB of PC3200 DDR SDRAM. Additional features include a RealTek audio codec with support for 6-channel sound and an S/PDIF output. A Gigabit Ethernet controller lets you quickly transfer data across a network at speeds up to 1000MBps.
2.8GHz Pentium 4 reached 3.27GHz on a 533MHz FSB, however. PCMark scores showed solid improvement. The systems CPU score rose from 6992 to 7542. Memory scores had been increasing much better since moving to faster FSB speeds, but we only saw modest gains with the 2.8CGHz as scores rose from 8511 to 8770. The HDD score was virtually unchanged at 1208. Final Word Compared to previous case studies, performance increases were very minimal. We saw a 20% increase in FSB speed and processor clock speed in our first case study. Here we only managed a 7.5% increase from 2.8GHz to 3.01GHz. We saw similar modest improvements to PCMark's CPU score as it increased a little more than 7.5% from 6992 to 7542. 3DMark relies on more than just the FSB and processor, so not surprisingly 3DMark scores saw even smaller improvements of a little more than 2%. In our last case study, we saw an 8.5% improvement in 3DMark scores. There's no doubt we're seeing diminishing returns as we increase our stock FSB and processor speeds. Compared to our earlier overclocking expeditions, however, overall performance still showed improvements. The 2.6C GHz we looked at previously on the same motherboard scored a 10698 3DMark score. Our 2.8CGHz P4 managed a 136point higher maximum 3DMark score. In this case as in the last, we managed to get the FSB up to 215MHz before we started running into problems. This may suggest the motherboard is actually reaching its limitations before the processors reach theirs. Whether we have any better luck with Canterwood 875 chipsets remains to be seen, but we're eager to move on and see where things fall. Next, we'll examine Intel's 3.0CGHz Pentium 4 running on Intel's Canterwood chipset.

by Chad Denton

BIOS Channel A Channel B ATX PSU Connector Northbridge (Intel 865G) Ethernet Controller Front USB Headers Southbridge (Intel ICH5R) Audio Codec SATA Connectors SPDIF Out
With everything stable, we entered the Frequency/Voltage Control menu once again and increased the FSB speed to 210MHz. This put us at 2.94GHz, just south of 3GHz. Again, we saw very modest gains of less than 50 points in 3DMark, but everything was at least running solidly. By increasing the FSB to 215MHz, we were able to get the 2.8CGHz up to 3.01GHz. 3DMark scores jumped almost 100 points to 10834. We werent able to move past 215MHz on the AX4SG Max in the last case study and surpassing that speed proved problematic for us again with the 2.8CGHz. Increasing the FSB to 220MHz set the processors clock speed at 3.08GHz and although the system was able to boot just fine, 3DMark could not successfully complete its benchmark. We returned to the Frequency/Voltage Control menu in the BIOS setup utility and increased the processors core voltage to 1.6 volts. Once again, Windows loaded

but 3DMark didnt complete successfully. Increasing the voltage to 1.7 volts caused the system to continually reboot. We did manage to make some modest gains. The faster FSB speeds mean a lower multiplier, which means smaller increases to the processors clock speed when we increase the motherboards FSB. Normally this is desirable, but its unclear here whether the motherboard or the processor is reaching its limit. The
Overclock Comparison 3DMark2001 SE
Intel 3.0CGHz Pentium 4 (800MHz FSB) Stock Performance 10728 Overclocked Performance Intel 2.8CGHz Pentium 4 (800MHz FSB) Stock Performance 10605 Overclocked Performance 10834 Intel 2.6CGHz Pentium 4 (800MHz FSB) Stock Performance 10480 Overclocked Performance 10698