ZOTAC GeForce GT 640 Review

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It’s no real secret that the mainstream and entry-level segment in graphics card has always belonged to AMD, since a really long time. I don’t know what it is, but Nvidia just couldn’t seem to deliver on the either performance or features, which is why AMD cards have always offered better value. That could soon be a thing of the past, though as they’ve now launched their highly anticipated mainstream GPU based on the Kepler architecture. The GT 640 first made its debut as an OEM only card and now Nvidia has finally released it for the retail market as well. We have ZOTAC’s offering of the GT 640, which follows along the same lines as Nvidia’s reference design. Let's see if Nvidia have finally managed to make a mainstream card that we can be proud of.

Small footprint

Small footprint


Design and Build
The ZOTAC GT 640 comes packaged in a compact box, which gives you a hint of how small the card actually is. The card and all the accessories are snugly packed in bubble wrap inside. The GT 640 looks like a typical HTPC card - puny! The small size and light-weight make it easier to to fit even in small cases. There reference design only has the heatsink covering the core, but ZOTAC has used a wider aluminium heatsink that even covers the RAM chips. The card could have been passively cooled, but ZOTAC have installed a tiny orange fan to disperse the heat better. The card is incredibly short as well and ends just after the PCIE slot.

Nvidia Surround ready!

Nvidia Surround ready!


Nvidia haven’t neutered the card too much and the GT 640 supports Nvidia Surround for up to four monitors. The ZOTAC card, however supports three due to the three display ports at the back. This is still a first for a mainstream Nvidia card, which is a big deal. ZOTAC has chosen a DVI-I, DVI-D and a miniHDMI port. They don’t bundle the adapter though, just a DVI to VGA adapter. Other contents in the box include an installation manual and a driver and utility disk. ZOTAC also throws in their Boost GPU tweaking program.

Small and compact

Small and compact


There’s no need for a extra PCIE power connector, since the GT 640 draws all of its power from the PCIE slot and since it doesn’t exceed 75W, there’s no need for one. Nvidia say the maximum power draw of the card on load is 65W, which means you can easily run this on any run of the mill PSU, though a good one is always recommended.

ZOTAC has stuck with the reference specifications as well from Nvidia and we have a core clock speed of 900MHz. Nvidia hasn’t skimped much on the cores as well and we have a total of 384 CUDA cores, which is lot if you look at their previous generation offerings. The card also comes with 2GB of GDDR3 memory clocked at an effective speed of 1800MHz. This much memory seems a bit of an overkill of regular use, but we guess the extra frame buffer will come in handy when you use it with multiple monitors. It’s a wonder why Nvidia didn’t do with faster GDDR5 memory?

Perfect for HTPC use and gaming too!

Perfect for HTPC use and gaming too!


Since this card is based on the GK107 core, you get most of the features of Kepler, but understandably, not all of them. For instance, GPU Boost is absent and so is TXAA. You do get the Adaptive V-Sync feature, which basically automatically toggles V-Sync on or off depending on the current framerate of the game. You can now have a multiple monitor set-up from just one card, something Nvidia has always lost out to AMD in the past with their Eyefinity tech. It also supports Blu-ray 3D and 3DVision. Other features include OpenGL 4.2, DX11, PCIE 3.0 and support for a maximum resolution of 3840 x 2160. Overall, the GT 640 seems like a very potent card on paper, even though it may not look the part in reality.


  • Processor: Intel Core i7-2600K CPU @ 3.40 GHz
  • Motherboard: GIGABYTE P67A-UD3R
  • Memory: G.Skill Ripjaws 8GB (4GB x 2) @1600MHz
  • Hard drive: Intel SSD 520 240GB (Boot Drive), WD Velociraptor 300GB (Secondary Drive)
  • GPU: ZOTAC GT 640
  • PSU: Cooler Master Silent Pro 1000W
  • OS: Windows 7 Ultimate 64-bit

Needless to say, the GT 640 runs incredibly cool and silent. The small fan is not at all noisy and does a decent job of keeping temperatures in check. When idle, the card runs at roughly 40 degree Celsius and during gaming, we recorded a maximum temperature of 54 degree Celsius, which is very good.

Since we didn’t have the HD 6670 or HD 7750 with us in time for the review, we’ve compared it to the next best thing, which is the HD 6850. This is slightly more expensive, but at least we can see where the GT 640 stands. Don’t be fooled by the size of the GT 640, as it pleasantly surprised us in the benchmarks. The biggest surprise was in Battlefield 3, where we were expecting sub-20 FPS, the ZOTAC GT 640 easily managed a healthy 29fps with all settings (except AA and AF) cranked up to Ultra, at 1600 x 900 resolution. This is not bad at all coming  from a card that looks like all it can do is decode 1080p movies. It also fared very well in Dirt 3, giving us playable framerates even at Full HD resolutions. Same goes for Batman: Arkham City as well. Metro 2033 was the only game where it really struggled and the framerates were not at all playable, so we haven’t included it.

3DMark 11
3DMark is a computer benchmarking tool created and developed by Futuremark Corporation to determine the performance of a computer's 3D graphic rendering and CPU workload processing capabilities. The latest version makes extensive use of all the new features in DirectX 11, including tessellation, compute shaders and multi-threading. We used the ‘Performance’ preset for this benchmark.


Battlefield 3
Battlefield 3 is a first-person shooter video game developed by EA Digital Illusions CE and is based on the new Frostbite 2 game engine. The game only supports DX10 and DX11, which enables enhanced in-game destruction with Destruction 3.0, creating more refined physics than its predecessor and quasi-realtime radiosity using Geomerics' Enlighten technology. The game is a visual treat and a nightmare for graphics cards, which makes it perfect for our test. We used the ‘Ultra High’ preset, Post AA – High, Blur – Full, Field of View  -  90, Level – ‘Fear no Evil’.




Crysis 2
Crysis 2 is a first-person shooter video game developed by Crytek and is based on the new CryEngine 3. Just like the first iteration of the game, Crysis 2 continues to be one of the best looking shooters to date. The settings used for this benchmark were ‘Ultra High’ preset in Adrenalin, DX11 and High-resolution texture patch.




Dirt 3
Dirt 3 is a rallying video game and the third in the Dirt series of the Colin McRae Rally series, developed and published by Codemasters. The game is extremely scalable and features DX11 tessellation effects. We used the built-in benchmark tool, along with ‘Ultra’ quality preset.




Batman: Arkham City
A sequel to Arkham Asylum, Arkham City features a more open world gameplay as well as DX11 elements. For this test, we disabled Nvidia’s PhysX, since it would be unfair to AMD’s cards. Everything else was maxed out.




Going into this review, I expected the pricing to be not more than Rs. 5,000, for which it’s a brilliant card that would trash the HD 5670 from AMD. However, ZOTAC has priced their GT 640 at Rs.7,800, plus taxes are extra. I didn’t expect this from a card that clearly looks like it belongs in the sub-5K price bracket. It’s quite expensive at its current asking price as there are other more powerful cards, like the HD 7750 and for a little more, the HD 6850 and HD 7770. If Nvidia and ZOTAC can lower the pricing to 5K, then it will make a killing, but not right now.

Name  -  Nvidia GT 640
Core Speed  -  900MHz
Fab Process  -  22nm
Type  -  DDR3
Amount  -  2GB
Speed  -  1800MHz
Bus Width   - 128-bit
DirectX Support  -  DirectX 11
Video Outputs
D-sub  -  No
DVI -   Yes (x2)
DisplayPort  -  No
HDMI  -  Yes


Upgrade to dedicated graphics and memory for unmatched high-definition visuals and performance with the ZOTAC GeForce GT 640. Hardware accelerated Blu-ray 3D playback enables the ZOTAC GeForce GT 640 to render stunning stereoscopic high-definition video with compatible displays and playback software. Advanced Dolby TrueHD and DTS-HD Audio lossless multi-channel HD audio bitstreaming ensures the ZOTAC GeForce GT 640 delivers rich audiophile-class audio to match the beautiful visuals. NVIDIA Surround technology with triple-display support enables the ZOTAC GeForce GT 640 to deliver unmatched gaming immersion and maximum productivity.


Name NVIDIA GeForce GT 640
Core Speed 900 MHz
CUDA cores / Stream processors 384
Fab Process 40nm


Type DDR3
Amount 2GB
Speed 1782 MHz
Bus Width 128-bit
DirectX Support DirectX 11

Video Outputs



Dimensions (W x D x H) 111.11 x 144.75 mm

After Sales Service

Warranty 2 Years

Published Date: Jun 15, 2012 09:41 am | Updated Date: Jun 15, 2012 09:41 am