has been making some inroads gaining acceptance into the enthusiast mindset. There was a time when that wasn't really the case, as they always lagged behind in features and overclocking ability when compared to others such as Abit, and Asus. This wasn't to say that their boards weren't any good; on the contrary, their boards have always been relatively stable.

Things have changed, as their boards are just as interesting as the top tier manufacturers, but a lot of their momentum the past 18 months has been due to the introduction of their Small Form Factor (SFF) PCs. Hardcore gamers scoffed at these boxes, but there was a legitimate market for these barebone rigs. They were small, easy to carry around or hide under a desk, as well as packing a lot of integrated features such as LAN, sound and video, all packaged in a nice aluminum case. This made for a nice PC for the corporate market, as well as aesthetically minded home users.

There were a few problems with the initial release, the SV24, such as noise, but more importantly the lack of upgradeable graphics, a problem that would come back in the later barebone packages. The integrated graphics wasn't exactly anything a 3D gamer would ever be interested in, and although there are many uses for the Shuttle SSFs, 3D gaming wasn't one of them.

A couple months ago, Shuttle released a barebone to answer that call, and today we'll be looking at the Shuttle XPC SS51. Almost every aspect of the barebone series has been upgraded, including the addition of an AGP slot. Before continuing, here are the &

Model SS51G

Chipset
North Bridge SiS651
South Bridge Sis962L

CPU: Socket 478
Intel Pentium 4/Celeron
478 pin package with 400/533MHz Data Bus Speed
Soft configuration FSB from 100Mhz to 166MHz

Form Factor: Flex ATX

Memory
2 x 184pin DDR DIMM
Support DDR200/266/333 un-buffer DDR SDRAM
up to 2GB capacity

Expansion Capability
AGP Slot X 1 Supports 2X / 4X AGP Device
PCI Slot x 1
USB port x 4
IEEE1394 x 3
5.25" Reserved Bay x 1
3.5" Reserved Bay x 2
(TWo HDs or Singel Floppy + Single HD)

Onboard Graphic: Integrated SiS651 VGA
VGA Memory cache up to 64MB
VGA driver

Audio: Realtek ALC 650
AC '97 v2.2 (supports 5.1 channel) compliant CODEC on board
Support Digital SPDIF In/Out
Audio Driver

Onboard LAN: Realtek RTL8139 Family PCI/Cardbus Fast Ethernet
10/100Mb Fast Ethernet LAN
Support Wake on LAN, Boot to LAN, PXE 2.0
LAN driver

USB 2.0: Integrated SiS 962 USB 2.0

Onboard 1394: VIA VT6306
Complies with 1394 OHCI specification revision 1.0
Support 400Mb/s, 200Mb/s, 100Mb/s data transfer rate

IDE interface
2 x Ultra DMA 133 IDE Channels Master from SiS962
80-pin Cable Backward Compatible Legacy ATAPI Devices
ATAPI IDE CD-ROM, CD-R, CD-RW, and LS-120 Supports

Case
Aluminum chassis 200(w) x 181(h) x 280(d)mm
Power supply 200Watts 110 / 230V
1 x 3.5" bay
1 x 5.25" bay
1 x 3.5" bay (Hidden)

Front Panel
2 x USB ports
1 x 1394 ports
1 x 1 x 5.25" bay
1 x 3.5" bay (Hidden)
SPDIF Out
1 x Mic-In
1 x Speaker-Out
Power-On
Reset

Back Panel Ports and Connectors
Power code/AC
1 x PCI slot
1 x AGP slot
1 x PS/2 Keyboard
1 x PS/2 Mouse
1 x VGA port
2 x Serial Port
2 x 1394 ports
1 x SPDIF In
2 x USB ports
1 x RJ45 port
1 x Front out connector
1 x Rear out connector
1 x Center/Bass connector

Thumbnails can be clicked to enlarge

The SS51 ships in an attractive box with a carry handle. Everything is neatly packaged, and surprisingly light. I know that the PC is tiny, but to be honest, I expected a larger box. Inside, you'll find the Shuttle SS51, power cable, and a smaller white box fitted within the foam pads.

There are quite a few accessories, including the IDE and floppy cables, the manuals, screws and the driver CD. I suggest downloading the latest drivers though, as the shipping drivers are woefully out of date.

The Case

The idea behind a SFF PC is to create a package that can be easily fitted into tight areas. Given that desk space is a valuable commodity these days, having a huge full tower on your desktop isn't a popular option. For the corporate user, under the desk is typically reserved for filing cabinets, or to accommodate those after-hours frolicking with the hired help, so many PCs need to be of the smaller variety to save on space. For the most part, other SFF cases serve that job well, but lack any "sex" appeal.

The Shuttle barebones are arguably the nicest SFF PCs to hit the market. They are a little larger than other SFF PCs, but no doubt, the look of an aluminum box will turn some heads. The XPC SS51 in particular is very attractive. The Flex ATX case measures a mere 200(w) x 181(h) x 280(d)mm. It really isn't much larger than a small toaster oven, and light enough that even when fully loaded, it's easy to carry under one arm.

One aesthetic feature that we liked is the front acrylic face plate. I suppose if you don't like it, you can easily remove it via the front screws. The SS51 we have came with a blue face plate, but these can be changed with new ones that you can make yourself, or by purchasing a different colour online. A small annoyance is that unless you stealth mod it, the floppy and CDROM drives will be badly mismatched colour-wise.

The power and reset buttons both have a nice feel to them. They don't feel very squishy, and make a reassuring click when depressed. They are accompanied by bright LEDs. The power LED is of the ultra bright variety, so no need to change that if you're a bright LED fan. Personally, I wasn't too wild about it since I prefer resting my PCs on my desk, and bright lights tend to annoy me. The HDD LED is a little more muted thankfully.

There are a slew of front panel connections, such as FireWire, USB, sound, and a SPDIF Out. This makes for much easier swapping of input devices, especially in my case where I do some late night gaming and plugging in headphones into the front of the case is much more convenient than battling with wires in the back.

There is no side or top panels with the SS51, but rather, it's kind of old school with the one piece top/side enclosure. Removing the three thumbscrews will allow you to pull back the cover, and slide it off at a 45 degree angle. Though it works well enough, I used to hate removing the cover this way, and I still do. Putting it back on does require some care, as a stray wire can interfere with reinstallation.

Given the lack of cooling fans, there are small holes on either side of the cover to allow some airflow. Unfortunately, there are no holes on the front, which may cause some issues with case cooling, depending on the hardware you may choose to install. We'll look more into the cooling later on in the review.

In the back, there are two fan exhausts present. The smaller one is for the power supply, whereas the larger one is the main cooling. Rather than using a wire grill, we have cutouts instead. I think a grill would allow for more airflow, so case modders may consider dremeling out the cutouts.

In the back, we also have the primary back panel for all your I/O needs. There isn't any external bracket, so for the multi-channel sound, you'll have to use the integrated sound software to configure the line-in and Mic-out to accommodate additional speakers.

There are two brackets available for additional PCI and AGP cards. I shouldn't say that in plural though, as you only have space for exactly one PCI and AGP card. One annoying feature is that if you ever have to remove or change a card, you'll have to unscrew the retaining screws for both to be able to lift the swinging retention plate.

Inside the case, you have the pre-installed motherboard, as well as the cooling and hard drive rack. Although one would think that such a small case would be difficult to work with, the Shuttle SS51 is actually a snap to get in and out of.

Removing a couple of small screws allows for the HDD rack to be removed. The stock rack can be outfitted with either a floppy, hard drive and optical drive, or two hard drives and an optical drive. As we've already mentioned, the lack of ventilation or front mounted fan would make me wary of running dual 7200RPM drives. The rack also has an IDE cable management clip, which will securely lock in the HDD cable. The clip isn't too strong though, so you'll have to be careful about snapping it if you forget to remove the cable while pulling the HDD rack out.

Cable management is explained in detail in the installation guide, and I would encourage you to give it a read. It's fairly straightforward, but it's nice that Shuttle thought out the best way to route cabling. Speaking of which, Shuttle includes a floppy cable, and both a short, one device IDE, as well as a rounded cable. Rounding the HDD cable isn't really that important, due the included clip mentioned earlier, but I wish they would have done likewise for the floppy connection.

The power supply is a mere 200W, but don't let that number deceive you as it should be adequate for this setup. At most, users will have two peripheral cards, a CPU, optical drive and maybe two hard drives. I can see that scenario as potentially posing a problem, but that will depend on the hardware. I run a 2.4GHz Pentium 4, with two hard drives, a Plextor writer, and a Radeon 9700 Pro without any problems.

There are plenty of connections, enough to suit most people, and like the IDE cabling, the PSU connections are routed nicely. Shuttle has stated that future FLEX ATX mobos will fit in the XPC chassis, but I couldn't find any information on the power supply itself. It's obviously Pentium 4 compliant, though with new P4s, I'm not certain if the PSU will be up to the task.

There is one issue I did have with the power supply though, it gets very hot. There's a small 40mm fan that exhausts the air, but as other 40mm fans I've looked at in the past, they are not that great. At least it's fairly silent though, and the case fan definitely overpowers the PSU fan in terms of noise.

I.C.E Technology

Introduced with the Shuttle SS40, the heatpipe returns again for the SS51. From what I've read, the heatpipe mostly addresses the noise issue as you no longer need a fan on top of your CPU heatsink. To best explain how this works, we'll look at it in steps&

1) Primary heatsink absorbs the heat
2) Heatpipes conduct heat away from CPU heatsink
3) Heatpipes are cooled by rear fan

The heatsink itself is a low profile aluminum heatsink with a copper base. It comes shipped preinstalled in the retention bracket. I'm not sure if it's the shipping, but our base was scratched pretty badly. I hope Shuttle would consider putting some kind of a protective film or tape in the future, but this was a bit of a disappointment.

The next couple of pictures are of the heatpipe itself. The heatpipe is surrounded by thin fins to help distribute the heat, which is in turned cooled down by a Sunon fan. The fan itself is of the speed control variety, but works in conjunction with the BIOS. You can set at which temperature(s) should the fan speed up. At its lowest settings, it was fairly quiet, but at the higher speeds, the noise is quite noticeable.

The clip is a snap to install, and applies a good amount of pressure on the heatsink. It does require two hands to put on and/or take off, but no tools are required. The fan shroud requires the removal of 4 thumb screws, and total assembly time of the cooling is about a couple minutes.

The I.C.E Technology looks interesting and all, but the question is& how does it perform? Leaving our BIOS settings at default, which is Fan Guardian Enabled (we'll look more into this later on), we took some tests and observed temperatures under full load. Needless to say, the temperatures weren't that impressive...

Maybe "weren't that impressive" is an understatement. It was downright scary to be running at 71C. Keep in mind that the default settings "turns on" speed control. I decided to turn that off and let it run at full bore.

Things were a little better, but not that great still. I'm not really certain how other reviewers managed temperatures less than 60C, but that wasn't happening here. You'll have to keep in mind that for testing, we only had one hard drive and the Radeon 9700 in here. If you were to load up with an optical drive and another hard drive with a fast CPU, I would expect you'll have similar temperatures as we've had.

What are my thoughts on the cooling performance? Honestly, I wasn't too thrilled with the I.C.E. Technology. I did test with the stock Intel, though getting it to fit wasn't so easy. The stock cooler is about 4C better than the best scores the heatpipe was able to manage. To improve the cooling, I would look into a faster spinning case fan, though be aware that the shroud, without modifications, won't allow for an oversized 80mm fan.

On the otherhand, the included Sunon fan is relatively quiet. It is noticable at full speed, but not unbearable. Since the SS51 is aimed more at the enthusiast, the noise probably won't be an issue.

The Motherboard

The SiS651 Northbridge powers the SS51 SFF. Considering it's a tiny Flex ATX mainboard, everything you can possibly need is present. It's a Pentium 4, 478 pin based board, and will support the newer Northwood "B" CPUs. Obviously, you can still drop in an older 478 CPU, and depending on the model, jack it up to 133FSB for a nice overclock. The integrated video is there for those who want to use it, and can cache up to 64MB of ram. It's automatically disabled when you install an addon AGP card, which I suspect will be 99% of you.

There are two memory slots, supporting up to 2GB of ram. The chipset supports PC2700, which should complement the faster CPUs. Be aware that Shuttle officially lists only 6 brands verified to work, so be wary if you got some generic stuff. We ran Crucial PC2700 without any issues.

Being such a compact board, you're not going to find any onboard RAID, though you can easily install an addon card in the PCI slot for that. There are just two IDE connections, and one floppy connection. It should be noted that I had trouble with bootups when I set the hard drive jumpers to "Master". Devices should be set to "Cable Select" to avoid the problem, which is basically extremely long IDE drive detection times.

Although it's a SiS board, VIA supplies the VIA VT6306 responsible for the firewire chores. This is a boon for multimedia enthusiasts, as firewire is the de facto standard for video.

The Sis962L Southbridge is responsible for the lower level functions of the board. USB2.0 support is present, and with the explosion of USB2.0 devices on the market, I'm sure you'll have a use for it. Naturally, it is backwards compatible with USB1.1 devices, so peripherals such as keyboards and mice won't have any problems with it.

Realtek makes its presence here with a couple of its chips. Networking is supported by the Realtek RTL8139, with supports 10/100 Ethernet. I wouldn't stress too much about the lack of giga-ethernet support as your cable or DSL modem will be the bottleneck.

The second Realtek part is the ever popular Realtek ALC 650. We've covered this part in other motherboard reviews, and have always been quite pleased with it. It supports 5.1 sound, and unless you're a true audiophile, I'm sure it'll suit your needs perfectly.

The BIOS

The Award BIOS, something I haven't seen for awhile, makes its way into the SS51. Their BIOS' have always been easy to navigate, and despite their merger with Pheonix, it remains easy. All the options are present, including the ability to enable or disable the onboard peripherals.

Naturally, to be accepted as a legitamate desktop replacement for enthusiasts, you have to have your tweaking options. There are ram options such as the speed and timings. More importantly, you also have dividers for your ram, which is handy for both overclocking, or if you have PC2100 ram, and don't wish to run at 166FSB.

For the CPU, you only have multiplier settings. This shouldn't be a concern since Pentium 4s are multiplier locked, but you'll have to be satisfied with FSB settings that cap at 165FSB. You can enter the clock speed in increments of 1, which should help in acheiving that perfect overclock (up to 165 of course).

Noticably missing is the lack of voltage settings. As overclockers will tell you, in order to attain stability with high overclocks, you may need to increase the voltage for various components. Sadly, you do not have that option here.

Overclocking

I did have some reservations about overclocking in such a small case, and dispite our lacklustre heatpipe performance, I decided to give it ago. We're using a Pentium 4 2.4GHz CPU, which has an 18x multiplier, so already, we were working with a high multiplier. I tried to acquire something a little slower, but wasn't able to in time for the review.

Right off the bat, I got courageous and attempted a 160FSB overclock. I was greeted with a nice blank screen, requiring a CMOS reset. I should warn you that unless you got tiny hands, there is no way to reach the jumper (for reset) unless you either remove the hard drive rack, or the video card (and possibly a PCI card, depending on the length).

I decided to back down and try a 140FSB overclock. Not surprisingly, this overclock was pretty easy, as it's only 7MHz over stock. We topped out at 142FSB. I did try to fit a Vantec Aeroflow into the case, but it interfered with the HDD cabling. I removed the hard drive rack, and tried overclocking again with the Vantec cooler, and I managed a 145FSB overclock, though running a PC without a hard drive is pretty much pointless.

Test Setup

Pentium 4 2.4GHz Northwood "B"
Shuttle XPC SS51G
2 x 256MB PC2700 Crucial
120GB Western Digital JB
Visiontek GeForce 4 Ti4600 (yes, it fits just fine)

Windows XP Professional
SiS AGP Driver 1.10A
nVidia Detonator 28.32

SiSoft Sandra
PC Mark 2002
Quake 3: Arena
Jedi Knight II: Jedi Outcast
3D Mark 2001SE

Rather than bogging you down with a dozen benchmarks at different speeds and resolutions, we're going to keep things simple. When applicable, only 640x480 scores will be displayed, as that resolution will eliminate the video card as the bottleneck.

We will be comparing benchmark scores to that of the MSI i845E Max2-BLR. I'm aware that the motherboard lacks DDR333 support, and we will be revisiting this subject at a later date.

SiSoft Sandra Memory

Despite the fact that DDR333 is supported by the SS51, performance lagged behind the MSI 845E. For the record, no memory tweaks were done to either motherboards, other than allowing them to run as fast as their supported speed.

Tweaking the ram wasn't terribly difficult, though I'm certain the 2 sticks of Crucial ram was the culprit. I set the ram timings to Fast, CAS2.5, and 1T, and crashed the system. However, these timings worked with only one DIMM installed. I read about this at another review, so it seems this problem still exists. With one stick, and the above timings (the best I could manage), Ram Int. improved to 2013, and Ram Float improved to 2009.

SiSoft Sandra CPU Arithmetic

SiSoft Sandra CPU Multimedia

CPU performance is very close for both platforms, though MSI continues to hold a slight edge in performance. Still, considering the mindset of most enthusiasts, where bigger is faster, the SS51 does very well to hold up on its own.

PC Mark 2002

Released by , we've decided to incorporate PC Mark 2002 into our motherboard and CPU testing for future reviews. It provides tests that benchmarks a PC for typical SOHO use. Here's a snip from their site:

PCMark"2002 is a completely new, multipurpose benchmark, suited for benchmarking all kinds of PCs, from laptops to workstations, as well as across multiple Windows® operating systems. This easy-to-use benchmark makes professional strength benchmarking software available even to novice users. PCMark2002 consists of a series of tests that represent common tasks in home and office programs. PCMark2002 also covers many additional areas outside the scope of other MadOnion.com benchmarks.

Continuing the trend we saw with SiSoft, the scores are close, but the overall winner goes to the 845E once again, with the exception of the memory score. Unlike the SiSoft memory results, the SS51 wins by a small margin. This was not a fluke, as I was able to reproduce the same results with subsequent tests.

Now, let's face it. There's an AGP slot, which means everyone is going to want to know the gaming performance...

3D Mark 2001SE

Not really one of my favorite benchmarks, but it's a popular, and free download. Benchmarks were run at default 1024x768, as I felt 640x480 is getting to be fairly pointless. The Shuttle does very well, though it trails the MSI by a little over 200 3D Marks. You'll have t keep in mind that this is a synthetic test, so 200 points isn't anything to go nuts about.

Quake 3 Arena

It's getting old, I know, but Quake 3 is still a decent benchmark for almost anything. For motherboards and CPUs, we run at the lowest settings and fire away. Scores are identical, which is good for the Quake 3 LAN player. You now have a killer box that you can carry with one arm (though we're assuming you have two, since strafe jumping is a little tough with one hand )

Jedi Knight 2

Jedi Knight is still a Quake 3 engine game, but heavily modified. It's extemely CPU taxing when compared to Quake 3 itself, so we feel it's a useful motherboard/CPU benchmark. The MSI is ahead by less than a frame per second, so we'll just go ahead and declare this a tie.

Final Words

Shuttle has hit a homer with the SS51, but not before whiffing at a couple of curve balls. As much as I enjoyed working with this barebone PC, there are a few concerns I have with it...

Heat is definitely a concern. It may just have been our test unit, but I think that the I.C.E. heatpipe could use a little work for the 2.4GHz+ CPUs. The power supply is in dire need of a better fan, as it is far to warm for my tastes.

The BIOS was lacking in voltage adjustments. I'm not going to knock the 165FSB ceiling as we never reached it with our CPU. If we had the ability to increase voltage, I'm pretty sure the overclocking would have been better. Keep in mind that we were dealing with an 18x multiplier, and anyone with a Northwood "A" can probably get decent 133FSB overclocks.

Given it's form factor, your upgrade path is fairly limited. With the power requirements of newer CPUs and video cards (the Radeon 9700 works fine), it may be tough to keep up as you may have with a more open design. Shuttle is committed to the XPC series, and plan to release motherboard upgrades as time goes on. Perhaps they'll take these things into account and have a list of recommended power supplies to help grow with the times.

There are a few things that kind of bugged me, such as the screws for the peripheals. The fact that you need to undo 2 screws, just to remove an AGP or PCI card is a bit of a drag. Also, I chose not to install a CDROM drive internally, due to heat concerns, so you have to be sure you screw the bezel back into the HDD rack with the right screws (in this scenario, I had an optical drive setup and changed my mind during testing). If not, the HDD rack won't go back in properly.

Now, I'm just really looking for things to complain about, but the truth is, this box is something I'm planning to use for a long time. The design is beautiful, and there should be some credit directed to the engineers for packing so many features into such a small PCB. Everything you can possibly need (or not need) is here, making for a very complete package.

Other than the exterior aesthetics, the interior work is superb. It is a tight case, but not hard to work with. Wires are already routed properly, and the wires you need to install are explained in the installation guide.

I did knock the heatpipe earlier, but I can applaud Shuttle's attempt to make a servicable cooling solution that is relatively quiet. With a more powerful fan, cooling would be much improved, though your noise levels will increase.

Given it's small size, and robust features, the usefullness of the SS51 is almost limitless. It can be a great LAN rig (with the proper video card), a corporate PC, a router, fileserver, or even a TiVO. Really, even when it's served it's purpose as a performance gaming PC, it can do almost anything else you want with it.

Lest we forget, the inclusion of an AGP slot is a major boon for gamers. I know big, and fancy modded cases go garner most of the attention at LAN parties, but you'll have to break your back moving it around. I'm sure if you pick up a SS51, you'll probably shock a lot of people when they see how much kick-ass performance the XPC packs. It'll be up to you to bring the skillz though.

Pros: Good performance, AGP slot, solid and beautiful construction, stable platform.

Cons: Runs hot, potentially limited upgrade path.

Bottom Line: No doubt, great things do come in small packages. You can pretty much call this the All-in-Wonder of barebone packages. It performs well, looks great, and includes everything you need to get going (minus the CPU/HDD/RAM/CD). What about AMD? The new XPC with the nForce2 is just around the corner...