Review: HD 4890 and GTX 275 offer great bang per buck
Our today's guest is Geforce GTX 275, the card announced on the same day as AMD’s Radeon HD 4890. These two cards promise to be fierce competitors, and if you’re planning on splashing out about €220 to buy a graphics card for gaming, any of these two will surely do you good.
While HD 4890 is currently AMD’s best single-GPU card, GTX 275 found its place between the GTX 260 and Nvidia’s fastest single-GPU card – the GTX 285. GTX 275’s GPU is made in 55nm, has 240 shader processors, uses 448-bit memory interface, and comes with 896MB of GDDR3 memory.
Gainward is one of the first Nvidia partners to come up with a nonreference GTX 275 card. Their card has a completely different PCB and cooling, and our today’s guest runs at reference clocks. GPU runs at 633MHz, the memory at 1134MHz and the shaders at 1404MHz.
GTX 275’s clocks are much higher compared to the GTX 260’s 575MHz core, 999MHz memory and 1242MHz shaders. Speed-wise, the GTX 275 is much closer to the GTX 285 where the GPU runs at 648MHz, the memory at 1240MHz, and the shaders at 1476MHz. In order not to jeopardize the GTX 285’s lead, Nvidia ended up using the 448-bit memory interface and 896MB of memory, whereas the GTX 285 uses the 512-bit memory interface and 1024MB of memory. Also, the GTX 285 has 32 ROP units whereas the GTX 275 has 28.
Unlike the reference card with dual slot cooling and one fan, Gainward uses two fans in order to maximize cooling efficiency and provide silent operation. We’ve already seen this cooling on some Gainward’s GTX 260 cards and we must admit it cools well and runs silent. Furthermore, if we compare it to the one on the HD 4890, we must admit it’s significantly quieter.
The cooler houses two large 8cm diameter fans connected to the 4-pin connector via one cable, and rpm regulation is a breeze. Note that both fans run at same speed.
Underneath the fan is a large heatsink with three heatpipes, and the plastic hood that holds the fans in place covers the entire card.
The picture below reveals that power components are cooled with a separate black heatspreader. Two fan design used by Gainward is efficient, but the heat released from dissipation surfaces stays in the case, whereas reference cooling pushes it out. This however should not be a problem if your in-case airflow is adequate.
The heatsink with three heatpipes is in direct contact with only the graphics core.
The picture below shows the three heatpipes going from the copper base to different parts of the heatsink. GTX 275 temperatures are higher than on the GTX 260, but Gainward’s cooling keeps them in check.
All 14 memory chips are on the front of the card, and are cooled by touching the aluminum block.
The card features a 448-bit memory interface, compared to the 512-bit on the GTX 280. Such a strange number is a direct result of disabling one ROP partition. The equation is pretty simple – each of the 8 ROP partitions on the GTX 280 is connected to the 64bit memory controller, and after a simple multiplication you’ll get the final number – 512. Since the GTX 275/260 has 7 ROP partitions, the same equation results in the 448-bit memory interface. Each of the memory controllers houses two memory chips, so the GTX 260 needs 14 chips to reach the 896MB capacity. One ROP partition comes with 4 ROP units totaling at 28 ROPs for the card.
The memory in question is Samsung’s 0.8ns memory, used by Gainward on their GTX260 GS and GTX260 GS GLH cards. This memory is rated at 1200MHz, and despite running at 1134MHz on the GTX 275, you’ll see that it’s easily overclockable to 1200MHz+.
Gainward used non-reference PCB with 4+1 phase PWM design. You may have noticed that the memory power components were moved to the opposite end of the card.
The card is powered via two 6-pin PCI-Express power cables.
The I/O panel features two dual-link DVIs and an S-Video out. Using the DVI-to-HDMI dongle, you’ll be able to bring video only to your HDTV, so if you want both video and audio you’ll have to bring sound to your graphics card first via a SPDIF cable.
The card comes with Realtek’s voltage regulator, which unfortunately doesn’t support software voltage adjusting.
Gainward GTX 275’s packaging is no different from GTX 260 or GTX 285’s. As a gift, you’ll get an activation code for 3D Mark Vantage.
All the accessories are in the box. DVI-to-HDMI dongle, DVI-to-VGA dongle, one power cable with dual 4-pin Molex-to-6-pin PCI Express adapter, TV out cable with HDTV support, SPDIF cable, driver CD and the user’s manual.