Specifications

The GeForce4 Ti 4200 is identical to the Ti 4600 in all regards other than operating frequency. It delivers the same DirectX 8.0 functionality through programmable pixel and vertex shaders. Obviously, the Lightspeed Memory Architecture II and Accuview anti-aliasing features are also included. As previously mentioned, the only difference is clock speed – 250MHz for the Ti 4200, 275MHz for the Ti 4400 and 300MHz for the Ti 4600. The Ti 4200 doesn’t require the same power circuitry as the faster 4400 and 4600 cards, so the board design differs slightly, yet the NV25 remains the central feature.

There are currently two versions of the GeForce4 Ti 4200. One sports 64MB of DDR memory effectively operating at 500MHz and the other houses 128MB of DDR running at 444MHz. Of course each design has its own strengths and weaknesses. Since the 64MB card features slightly faster memory, it is usually able to outperform the 128MB variant. However, as the quantity and quality of cached textures increases, 64MB of memory proves insufficient. So if you anticipate frequent video card upgrades, a 64MB card will best suit your needs. Conversely, the 128MB version will work well for the long haul.

ABIT plans to offer the Siluro GF4 Ti 4200 OTES in both 64 and 128MB configurations, though the card we are looking at today comes with 64MB. Rather than adhering to NVIDIA’s reference design, ABIT uses 3.6ns Hynix memory modules rated for operation at 555MHz. Consequently, NVIDIA’s design calls for a 250MHz core and 500MHz memory clock, but ABIT has superceded that level of performance with a core clocked at 275MHz and a memory speed of 550MHz.

ABIT Siluro GeForce4 Ti 4200 OTES

The back of the card

Sowing the OTES

Under normal circumstances, increasing the core and memory frequencies would be a difficult task. NVIDIA guarantees the core will run at a given speed, so surpassing that limit introduces the possibility of product failures and inevitably, warranty returns. ABIT’s secret is an innovative cooling method dubbed OTES (the acronym stands for Outside Thermal Exhaust System). The base of the ‘exhaust system’ is a large, conductive copper plate that removes heat from the GeForce4 GPU. A liquid-filled, copper heat pipe is soldered to the conductive base running a constant condensation-evaporation cycle, theoretically removing heat faster. As heat is absorbed from the GPU, the liquid begins to boil forcing hot vapor to the other end of the pipe. Then, heat is released from the upper part of the cylinder after being exposed to cooler air. The liquid returns to the bottom of the pipe (generally under the force of gravity) where the cycle begins anew. ABIT uses a copper fin heat sink in conjunction with a 7200 RPM ball-bearing fan to accelerate the process. The plastic covering the fan purportedly creates a sealed environment so that all of the fan’s air output is directed through the heat sink. As you can see, ABIT completely covers the GPU with thermal compound to ensure rapid heat transfer.

Thermal paste on the GPU, nice touch!

Apparently, ABIT has learned from eVGA’s failed venture into active cooling. With the OTES system, all of the heat absorbed from the copper base is quickly directed away from the graphics processor and none of the memory modules are subjected to the heated copper pipe. The result is a truly effective cooling system. I was able to obtain a non-contact thermometer manufactured by Raytek featuring 8-point circular laser sighting to test the OTES system. In scanning the Siluro GF4 Ti 4200 OTES board, the highest temperature reading was 131 degrees Fahrenheit, which happened to be near one of the memory modules. ABIT’s original Siluro GF4 Ti 4200 64MB card, clocked at a more conservative 250/500MHz, registered a searing 156 degrees. Even the reference GeForce4 Ti 4400 had a 143 degree hot spot.

Cooling system up close