Model: Siluro GF4 Ti4200 OTES
Price: (Street) $160
Abit's Siluro GF4 Ti4200 OTES graphics card
CPU OVERCLOCKING has gotten to the point where just about every PC enthusiast is doing it. Back in the day, an overclocked processor had you riding the bleeding edge, even if you were only running a few percent faster than stock. Now, overclocked processors are everywhere, leaving many enthusiasts searching for a new frontier to conquer. Since the quest for higher gaming frame rates so often drives the overclocking itch, taking on graphics cards seems like the next logical step.
Software utilities that allow you to ramp up the clock speed of your graphics card have been around for years, but now Abit is upping the ante with the Siluro GF4 Ti4200 OTES, a graphics card that comes overclocked right out of the box, with a radical new cooling system thrown in for good measure. The card's Outside Thermal Exhaust System is unlike anything I've seen on a production graphics product, and it's Abit's latest stab at pushing the bleeding edge of system performance.
Is this factory-overclocked GeForce4 Ti 4200 really all that? Is OTES the shape of things to come for graphics cooling? We've examined the card, overclocked it, and tested its 3D performance and noise levels to find out. Read on to see what we found.
Abit's Siluro GF4 Ti4200 OTES
The Siluro GF4 Ti4200 OTES is based on NVIDIA's venerable Geforce4 Ti 4200 GPU, a favorite of budget-conscious gamers looking for frame rates without having to empty their wallets.
A GeForce4 Ti 4200 GPU lurks under the goo
Although the Siluro GF4 Ti4200 OTES is actually based on the GeForce4 Ti 4200 GPU, the card's core and memory clock speeds match those of the faster GeForce4 Ti 4400. Here's how the respective fill rates and memory bandwidth shape up:
||GeForce4 Ti 4200 64MB
||Siluro GF4 Ti4200 OTES
|Core clock (MHz)
|Peak fill rate (Mpixels/s)
|Texture units per pixel pipeline
|Peak fill rate (Mtexels/s)
|Memory clock (MHz)
|Memory bus width (bits)
|Peak memory bandwidth (GB/s)
The Siluro GF4 Ti4200 OTES is overclocked right out of the box, and the boost in clock speeds gives the card minor advantages in fill rate and available memory bandwidth. We'll see how these minor clock speed differences affect the card's performance a little later.
Abit's graphics boards are usually pretty stylish, but the Siluro GF4 Ti4200 OTES comes on a dark brown PC that doesn't exactly cry out to fashion-conscious enthusiasts. Sure, the brown matches the card's copper-colored metallic bits, but in an aluminum case with a red motherboard, blue sound card, brightly-colored rounded IDE cables, and a fluorescent cold cathode, the Siluro GF4 Ti4200 OTES sticks out more than an Itanium at a LAN party.
A lovely shade of, er, brown
You can't tell from the picture, but the Siluro GF4 Ti4200 OTES is actually slightly longer than a standard GeForce4 Ti 4200 card. This extra inch or so doesn't create motherboard compatibility problems, at least not on all the motherboards I have in house. Then again, all the motherboards I have also accommodate the gargantuan GeForce4 Ti 4600.
Four screws hold it all together
Because there's quite a bit more to the OTES cooling system than a standard GPU cooler, a four-point mounting bracket holds the cooling system in place. The bracket, and entire OTES setup, is easily removed with just four screws, and the screws themselves are designed such that you can't over-tighten them. Restricting how much you can screw down the mounting bracket also ensures that the metal bracket's arms don't make contact with any of the components on the PCB. The center of the bracket rests on a rubber spacer to prevent any conductive PCB contact.
Hynix chips rated for 275MHz
Hynix supplies the memory chips for the Siluro GF4 Ti4200 OTES. Since the card actually runs at GeForce4 Ti 4400 speeds, the memory chips are rated for 275MHz. So, while the card uses a GeForce4 Ti 4200 GPU overclocked to Ti 4400 speeds, the memory is actually running in-spec at 550MHz DDR.
Curiously, there's no passive or active cooling present on the Siluro GF4 Ti4200 OTES's memory chips. I would have thought that, with a card so obviously designed with the overclocking enthusiast in mind, at least some consideration would be given to memory cooling. Switching the memory over to BGA chips is probably too extreme an expectation for a card at this price point, but a few memory heat sinks would have fit in nicely with the whole theme.
Then again, at least in my own testing, memory heat sinks don't necessarily guarantee better overclocking results. In our GeForce4 Ti 4200 round-up, cards with memory heat sinks didn't have an overclocking advantage over those without.
Although the card we're reviewing today is a 64MB model, the Siluro GF4 Ti4200 OTES also comes in a 128MB flavor, which I'd recommend given the results of our recent graphics memory size comparison.
Philips SAA7104E for video output
Like the majority of GeForce4 Ti 4200-based graphics cards I've seen, the Siluro GF4 Ti4200 OTES uses Philips' SAA7104E encoder chip. The chip is capable of NTSC/PAL output resolutions up to 1280x1024, and also supports HDTV output. However, the SAA7104E is just an encoder chip, which means it's not capable of decoding incoming video feeds.
And now for something completely different
The Siluro GF4 Ti4200 OTES features a standard array of video output ports, including VGA, DVI, and S-Video outputs, but it actually spreads those ports over a double-wide PCI back plate to make room for the OTES exhaust duct. The back-plate will steal the PCI slot right next to your AGP card, which will be a problem if you use all of your motherboard's PCI slots. The unique back-plate layout and size also makes the Siluro GF4 Ti4200 OTES incompatible with Shuttle's SS51G, whose PCI slot is actually on the opposite side of the AGP slot. I haven't personally had the chance to check out other AGP-equipped small form factor systems, but my guess is the OTES will create compatibility problems in other mini-PCs.
Two story, three output, with a view
Because the Siluro GF4 Ti4200 OTES's S-Video and VGA outputs are on the back plate's second tier, they can't be mounted flush with the PCB. To work around this problem, there's a small riser card that feeds the analog outputs. At first, the riser board had me worried about video signal quality degradation, but the card's analog output is no worse than other GeForce4 Ti 4200 cards I've tested.
Abit's Outside Thermal Exhaust System is quite a bold step in cooling for a graphics card from a major manufacturer. The system utilizes a copper base in conjunction with a heat pipe, fin heat sink, high-speed blower, and plastic cover to efficiently funnel heat away from the GPU and out the back of the card. Since OTES differs so much from conventional graphics cooling, I'll break down each of the components one by one.
A plastic cover seals it all insort of
Abit's OTES uses a tight-fitting plastic cover to seal off the cooling system's internals and duct air effectively through the blower, around the copper base, and out over the heat sink toward the rear exhaust port. The plastic cover doesn't create a perfect seal, but it should be enough to effectively direct air with only the odd leak here and there.
There she blows
To drive air through the cooling system, Abit uses a 7,200 rpm blower; even most processor fans don't spin that fast. To its credit, the blower features two ball-bearings, which should extend the life of the fan and reduce the noise it produces. Still, anything spinning at 7,200 rpm is going to be loud. How loud? Hold tight, we'll get to that.
An excellent goo application
The cooler's primary contact with the GPU is its copper base, on which Abit has diligently applied just the right amount of thermal compound. The base itself is perfectly smooth, so it should provide an efficient thermal transfer medium. Since the base is actually quite a bit bigger than the GPU itself, and since it extends all the way to the back of the card, there are a few rubber spacers to prevent any kind of conductive contact with PCB components.
Fins and a heat pipe
Air is expelled from the cooling system over a set of copper cooling fins that stretch from the blower all the way to the card's rear exhaust port. A heat pipe also stretches between these fins and the copper base, but the pipe's small diameter, and the fact that it doesn't connect directly to the GPU, has me questioning just how essential it is to the whole cooling operation.
Set up a wind mill, if you'd like
The final component of the OTES is the rear exhaust port, which releases warm air from the system out through the rear of the card. The air coming out of the exhaust port is noticeably warmer than room temperature, and there's quite a bit of turbulence, too. The streamers are my own addition, but they nicely illustrate just how much wind the OTES generates.
A bundle of joy
Abit doesn't mess around with the bundle for the Siluro GF4 Ti4200 OTES. They give you everything that you need, without any extra fluff, which is exactly how I like it. In addition to a requisite driver CD and copy of SiluroDVD, a rebadged version of Intervideo's WinDVD software, the bundle includes a full cable set and that all-important DVI-to-VGA adapter.
My perfect bundle
Cables might seem like a minor thing, but I really have to give Abit some love for the nicest cables I think I've ever seen included with a graphics card. The composite video, S-Video, and even Y-cables are thin, flexible, and downright sexy. Abit hasn't skimped on cable length, either; both video cables will reach video equipment six feet away.
Overclocking with OTES
The Siluro GF4 Ti4200 OTES comes overclocked to GeForce4 Ti 4400 speeds right out of the box, but don't think that was going to stop me from turning up the clock speed a little. In testing, I was able to get the card stable and artifact-free with core and memory clock speeds of 315 and 585MHz, respectively. A 45MHz core overclock is nothing to sneeze at, but honestly, I was hoping for something more exceptional. The memory overclocking results are less than impressive as well, especially since the memory chips are rated to run at 275MHz.
I also overclocked Abit's vanilla Siluro GeForce4 Ti 4200, and that added insult to injury. The vanilla card, with stock cooling, ran stable with core and memory clock speeds of 320 and 620MHz, respectivelyboth faster than the OTES card. What's especially remarkable is that the vanilla Siluro uses memory chips rated to only 250MHz.
Just for kicks, I swapped the OTES apparatus for a stock cooler on the card just to see what would happen. To my surprise, the card was still stable and artifact-free running with a 315MHz core clock speed. The limitation here is the GPU itself, which probably won't make it past 315MHz with any kind of air cooling.
In all fairness, Abit's OTES probably allows them to more consistently overclock GPUs to the 275MHz stock speed for these cards. Also, the GPU should run a little cooler than it would with stock cooling, which should make for a more stable setup with greater longevity.
In the end, our results illustrate how much successful overclocking requires luck, pixie dust, and usually a small sacrifice. There are no guarantees when running hardware out of spec.
Core and memory clock speeds are going to be the defining factors, at least as far as our 3D performance benchmarks go. The Siluro GF4 Ti4200 OTES occupies the middle of the pack, both at stock and overclocked speeds. At least in 3DMark2001 SE, there benefits of overclocking are fairly consistent once we get out of extremely low resolutions.
The Siluro GF4 Ti4200 OTES's 7,200 rpm blower doesn't look like the quietest cooling solution, and it's not. To give you an idea just how much noise the card makes compared to a stock GeForce4 Ti 4200 cooling fan, I did some noise level testing with my trusty decibel meter. Two measurements were taken while the test system cranked through 3DMark2001 SE, one in close proximity, four inches away from the rear exhaust port (though not directly in the path of air flow), and one four feet away from the test system to get an idea of overall noise levels for the room.
Up close, the OTES is just over five dB louder than a stock cooling fan, which isn't as trivial a margin as this graph suggests. More on that in a second.
Even a full four feet away from the test system, Abit's OTES produces noise levels more than four dB higher than a stock cooling setup. I've listened to both cooling setups at length, and I can tell you that graphing the results on a bar chart against the logarithmic decibel scale doesn't do the difference in actual noise levels justice. Sound intensity can also be expressed in terms of watts per square meter, and I've converted the decibel readings to illustrate better the difference in noise intensity that you'll hear between the two cooling systems.
When we do away with the logarithmic decibel scale, how much louder the OTES is up close becomes much clearer. With our close proximity measurement, it's more than three times as loud as a stock cooling setup.
As we move farther away from the test system, the sound intensity drops, but the stock video cooler is still a much quieter setup.
I'm quite used to sleeping next to all manner of humming, buzzing, and whirring hardware, but the Siluro GF4 Ti4200 OTES was just too much. I actually ended swapping the card out if I left my test machines crunching Folding@Home at night.
If the OTES had allowed me to reach previously unattainable GPU clock speeds, I might be more excited about the product. Sadly, it didn't, so all I'm left with is a really noisy factory-overclocked GeForce4 Ti 4200 that takes up an extra PCI slot. Honestly, I don't mind losing a PCI slot, but I don't want to have to turn up my music just to drown out my graphics card's cooling system.
Noise complaints aside, it's nice to see a factory-overclocked card hitting the market. At $160 on Pricewatch, the Siluro GF4 Ti4200 OTES 64MB is about $20 cheaper than the nearest GeForce4 Ti 4400, but the Ti 4400 does have 128MB of memory. Currently, there aren't any 128MB OTES cards up on Pricewatch, so a more direct street price comparison with the GeForce4 Ti 4400 is impossible to make.
Don't get me wrong. I love the OTES idea, and it's something that I'm eager to see Abit further develop in future products. The cooling system has the potential to keep the GPU cooler than stock cooling solutions, which certainly bodes well for the longevity of an overclocked GPU. And, though I found this particular implementation far too noisy to justify the incremental boost in clock speeds and performance, I'm hopeful that future revisions can offer better performance with lower noise levels.
If your system already sounds like a 747 taking off, you'll probably be quite happy with the Siluro GF4 Ti4200 OTES, especially if you have a fetish for sexy video cables. Otherwise, it's probably better to go with a quieter GeForce4 Ti 4200, perhaps even Abit's own vanilla Siluro GeForce4 Ti 4200.