Shuttle’s XPC SB75G2 small form factor system

That trend continues with the XPC SB75G2, which mates Shuttle’s classic “G2” chassis with Intel’s high-end “Canterwood” 875P Pentium 4 chipset. The SB75G2 is Shuttle’s sixth XPC system based on the G2 chassis, and with the recent introduction of new “G4” systems, the SB75G2 may also be Shuttle’s last G2 cube. If the SB75G2 is indeed Shuttle’s last G2, the chassis is certainly going out with a bang. Read on for the goods on Shuttle’s Canterwood cube.

The specs
As usual, we’ll start with a quick look at the SB75G2’s spec sheet.

On the surface, the SB75G2 looks like a pretty standard 875P implementation, but Shuttle’s take on Intel’s Canterwood platform has a few unique twists that I’ll be highlighting as we move along. Speaking of moving along, let’s get started with the pictures of the all-black SB75G2.

Thinking outside the box
Maybe it’s nostalgia talking, but I think Shuttle’s G2 faceplate is easily the company’s most attractive cube treatment.

Unfortunately, as good as the black face plate looks with its drive bays empty, a beige optical drive completely ruins the SB75G2’s aesthetic. 5.25″ or 3.5″ drives don’t necessarily have to be black to match, though. The G2 faceplate’s silver buttons and screws nicely accent shiny silver memory card readers and optical drives. Heck, even a silver floppy drive would look decent.

Shuttle’s competitors have incorporated an array of hinged and sliding drive bay covers to prevent mismatched optical drives from ruining a cube’s appearance, but the G2 faceplate has no such luxuries. I’m a little puzzled about why Shuttle’s designers haven’t come up with a drive bay cover of some kind.

Moving along, the G2 face plate also has a cluster of audio, USB, and Firewire ports. Analog headphone, microphone, and line-in ports populate the bottom of the face plate along with a couple of USB ports and a single Firewire port.

Because small form factor systems tend to have cramped internals, cooling and air flow are always concerns. To improve ventilation, Shuttle gives the SB75G2’s side panels some fancy mesh screens that actually look pretty trick. The screens also give outsiders a peek inside the system, but without any filtering, they also let dust inside the system.

Around the back, the SB75G2 has a full suite of ports and plugs. The Canterwood chipset doesn’t have an integrated graphics core, so the SB75G2 has no video output ports. This lack of video ports leaves plenty of room for a couple of serial ports, PS/2 keyboard and mouse ports, an Ethernet jack, Firewire port, and four USB ports.

Because its analog audio inputs are all located at the front of the system, the SB75G2’s rear analog output ports don’t have to do double duty. Analog out ports are available for front, rear, and center channels, and the system even has a couple of S/PDIF ports for digital audio input and output. I’m not sure why Shuttle put the SB75G2’s S/PDIF all the way in the top corner, especially since the port cluster has room to spare, but the odd placement doesn’t create any problems.

The belly of the beast
The SB75G2’s black exterior is certainly sexy, but inner beauty is supposed to be what’s important, right?

The view from above…

and from the side

The SB75G2’s internals look cluttered, but there’s really no way around a little mess when working with a small form factor platform. Fortunately, there’s just enough room around each of the system’s slots and sockets to make component installation possible in such cramped quarters.

As tight as the SB75G2 is, there’s still plenty of room around the motherboard’s 478-pin Pentium 4 socket.

Because the XPC form factor offers such little board real estate, the SB75G2 has only two DDR 400 DIMM slots. Most Canterwood boards have four DIMM slots organized in two DIMM pairs. Having only two slots limits the SB75G2’s memory upgrade potential, but when you’re dealing with a smaller form factor, some sacrifices have to be made. Shuttle has, however, blessed the cube with plenty to storage potential: two IDE ports and two Serial ATA ports.

Like the rest of Shuttle’s cubes, the SB75G2 follows a non-standard PCI/AGP slot layout that puts the AGP slot on the outside edge of the board. Without cutting up the SB75G2’s side panel, the system isn’t compatible with double-wide graphics cards like NVIDIA’s GeForce FX 5800, 5900, and 5950 Ultra boards.

Shuttle does what it can to clean up the SB75G2’s internals by routing power cables around the system’s frame. The short power cord on the SB75G2’s 250W power supply is even sheathed to tidy things up.

To help making working inside the SB75G2 a little easier, the system’s drive bay cage is removable. The cage has a couple of 3.5″ bays, so it’s technically possible to run a pair of hard drives in addition to a 5.25″ optical drive. However, because of the system’s cramped internals and limited air flow, heat could be a concern with more than one hard drive.

Ice, ice, baby
Shuttle’s ICE cooler has to be one of the most gorgeous heat sinks I’ve ever laid my eyes on. Check it out:

The ICE cooler is an elegant array of fins and heat pipes built up on a copper base plate that should keep even a Pentium 4 at 3.2GHz running nice and cool.

Considering the SB75G2’s tight internals, it’s really quite impressive that the ICE cooler is a snap to install. The cooler’s heat sink clip is easier to use than most Pentium 4 heat sink retention systems, which speaks volumes for Shuttle’s intelligent engineering efforts.

An 80mm Sunon fan keeps the SB75G2 nice and cool. The single exhaust fan is responsible not only for expelling heat from the ICE processor cooler, but also for keeping ambient system temperatures under control. The SB75G2’s 80mm Sunon is a variable speed fan controlled by the motherboard’s BIOS, which helps make the system as quiet as its stealthy black exterior. I’ll touch on the BIOS’ fan speed controls in a moment, but before I get into that, I have to praise Shuttle’s attention to detail with the fan shroud.

In an attempt to keep the SB75G2 as quiet as possible, Shuttle puts rubber washers on the fan shroud’s contact points to cut down on vibration. There’s not much Shuttle can do about system noise generated by fans, hard drives or graphics chip coolers, but they’ve at least tried to eliminate noise from the system’s most vibration-prone part.

The fan’s rubber dampers work so well on the system fan that I’d like to see them used in a few other places inside Shuttle’s XPC chassis. It would really be nice to have a few rubber washers for the system’s drive bays to cut down on optical and hard drive vibrations. It’s the little things that count.

The BIOS
The SB75G2 looks great on the outside and is bristling with chips on the inside, but it’s the system’s BIOS that brings it all together.

Enthusiasts have access to a full range of memory and AGP tweaking options in the SB75G2’s BIOS. If you’re looking to run a pair of low-latency DDR400 modules in the system, the SB75G2’s BIOS is well equipped.

The SB75G2’s cramped internals and limited air flow don’t exactly lend themselves to overclocking, but the cube’s BIOS can push the front-side bus all the way up to 250MHz in 1MHz increments. The BIOS can also lock down the PCI and AGP busses to keep them in spec when the system bus is pushed beyond 200MHz.

While the SB75G2’s front-side bus goes all the way up to 250MHz, the BIOS only offers processor voltages up to 1.5875V. Available processor voltages do go as low as 0.8250V in 0.025V increments, but 1.5875V is a little weak for a CPU voltage ceiling. DRAM voltages are available between 2.65 and 2.75V, and AGP voltages are offered between 1.55 and 1.65V, both in 0.05V increments.

It’s disappointing that Shuttle hasn’t incorporated any safety features into the SB75G2’s BIOS. Considering the cube’s limited air flow and dependence on a single fan to keep everything cool, a fan failure has potentially disastrous consequences. I’d really like to see Shuttle incorporate CPU temperature or fan failure-based alarm and shutdown conditions for the cube.

Users can, however, select from five different fan speed options to balance effective cooling with acceptable noise levels. SB75G2 owners can set their own temperature thresholds for the “smart fan” or use one of Shuttle’s four pre-defined fan speed states.

Our testing methods
All tests were run three times, and their results were averaged, using the following test systems.

Today we’ll be looking at the XPC SB75G4’s performance against another Canterwood platform, Chaintech’s Zenith 9CJS. Both systems used identical components, memory timings, and drivers.

We used the following versions of our test applications:

• SiSoft Sandra Standard 2003
• ZD Media Business Winstone 2002 1.0.1
• ZD Media Content Creation Winstone 2002 1.0.1
• TCD Labs HD Tach v2.61
• Futuremark 3DMark03 Patch 330
• Quake III Arena v1.31
• Unreal Tournament 2003 demo
• RightMark Audio Analyzer 5.1
• RightMark 3D Sound 1.0
• Cinebench 2003
• Sphinx 3.3

The test systems’ Windows desktop was set at 1024×768 in 32-bit color at a 75Hz screen refresh rate. Vertical refresh sync (vsync) was disabled for all tests. Most of the 3D gaming tests used the high detail image quality settings, with the exception that the resolution was set to 640×480 in 32-bit color.

All the tests and methods we employed are publicly available and reproducible. If you have questions about our methods, hit our forums to talk with us about them.

Memory performance

The SB75G2’s memory bandwidth and access latency scores leave a something to be desired. I used the same DDR400 DIMMs and 2-6-3-2 latencies in both systems, but the cube’s pulling up a bit short. Less aggressive memory timings on the SB75G2 are likely responsible for the lower performance.

Disk controller performance

For all intents and purposes, the SB75G2’s disk controller performance is spot on for Canterwood’s ICH5R.

Business and Content Creation Winstone

The SB75G2 is a little behind in the Winstone tests, but not by much.

Gaming

The SB75G2 is a little off the pace in our gaming tests, too. In most tests, the difference isn’t more than a couple of frames per second. However, the cube is about 10% slower in the bandwidth-loving Quake III Arena.

Cinebench rendering

In Cinebench, the SB75G2 is again just a little bit slower than a full-sized Canterwood platform.

Sphinx speech recognition

Sphinx loves memory bandwidth, so it’s no surprise that the SB75G2 is a little off the pace here.

Audio performance
The Zenith 9CJS uses VIA’s Envy24PT audio chip, which makes for an interesting contrast with the XB75G2’s ICH5R south bridge/ALC650 audio implementation.

With 2D audio, the SB75G2 uses more CPU time than our Zenith 9CJS. That carries over to hardware 3D audio acceleration, where the SB75G2 consumes double the CPU cycles of the Envy24PT. However, if we switch over to software audio acceleration, the SB75G2 actually uses fewer CPU resources than the Zenith 9CJS.

Audio quality
For RightMark’s audio quality tests, I used a Terratec DMX 6fire 24/96 for recording. Analog output ports were used on all systems.

To keep things simple, I’ve translated RightMark’s word-based quality scale to numbers. Higher scores reflect better audio quality, and the scale tops out at 6, which corresponds to an “Excellent” rating in RightMark.

RightMark classifies the SB75G2’s frequency response as “very good” for both the front and rear output ports, but the cube’s dynamic range isn’t quite as strong. In casual listening tests, the SB75G2’s integrated audio really doesn’t stand a chance against true 24-bit sound cards like M-Audio’s Revolution 7.1 or Creative’s Audigy 2. Anyone serious about audio fidelity will want to fill the SB75G2’s single PCI slot with a sound card.

Peripheral speed
Our USB 2.0 and Firewire transfer speed tests involve transferring a mix of files totaling 1.89GB from a USB 2.0/Firewire external hard drive enclosure to the test system. The hard drive enclosure was connected to a 7200RPM Maxtor 740X-6L hard drive.

In our USB 2.0 and Firewire transfer tests, the SB75G2 is every bit as fast as our other Canterwood platform.

Our Ethernet speed tests involve downloading the same 1.89GB batch of files used in our USB and Firewire tests from a file server based on Intel’s Springdale platform. The Springdale board’s CSA-attached Gigabit Ethernet port was used, and both the server and test systems were connected to a 100Mbps Ethernet switch.

The SB75G2’s lack of CSA-attached networking doesn’t hurt the SB75G2 at all in our Ethernet transfer test, but keep in mind that we’re only using a 100MBps network.

Overclocking
Cubes don’t really lend themselves to overclocking, but we pushed the SB75G2’s front-side bus anyway. I was able to get the system stable with a front-side bus speed of 225MHz, which isn’t too shabby considering the cube’s limited air flow and cramped internals; our full ATX Canterwood platform could only handle front-side bus speeds 5MHz faster.

Overclocking success is never guaranteed and can depend as much on cosmic variables as individual system components and a little bit of luck. Just because my SB75G2 was stable with a 225MHz front-side bus doesn’t mean that every one will hit those speeds, or that some won’t be comfortable with higher speeds. Your mileage may vary.

Overclocking gives our SB75G2 a nice little performance boost, but without fan failure or CPU temperature-triggered shutdown conditions, I’d be hesitant to run the cube out of spec.

Conclusions
The all-black XPC SB75G2 is a stylish and stealthy take on Shuttle’s monstrously diminutive form factor, and with Canterwood inside, this cube is riding the cutting edge of Pentium 4 chipset technology.

Only a couple of small flaws keep the SB75G2 from perfection. First, the system’s performance is a little slower than what we’ve come to expect from Canterwood platforms. With more aggressive memory timings in a new BIOS, Shuttle might be able to bring the SB75G2 up to speed. The SB75G2’s second flaw is really one that plagues all of Shuttle’s XPC systems: the lack of a drive bay cover. I’d really like to see one, at least as an option.

Small flaws aside, the SB75G2 is an impressive little cube. The SB75G2 is currently the only Canterwood-based cube on the market, and it’s packing one of the quietest, slickest cooling systems I’ve seen in a small form factor (or full-size) system. Unlike some manufacturers, Shuttle doesn’t bundle remote controls, LCD screens, or a lot of other extras with its XPC systems, but the SB75G2 can easily get by on the merits of its features, performance, and form factor.

At $355, there’s no dodging the fact that the SB75G2 is very much a premium product with a premium price tag. Canterwood doesn’t come cheap. This XPC model is a little pricey for mainstream users, especially since it lacks integrated video, but enthusiasts looking to squeeze every last drop of performance out of the Pentium 4 processor should do well with Shuttle’s latest Black Betty.