Technical Data / Specifications

With the MSI GeForce GTX 770 Lightning OC you get a card which features a custom PCB as well as a custom cooler. The ASIC quality measured on our sample was 75.0 % which is quite low but it's good news since overclockers will have more fun feeding this beast with liquid nitrogen.
About ASIC quality:



MSI is using the latest NVIDIA Kepler GK104-425-A2 chip, which is manufactured by TSMC with the latest 28 nanometer process technology. With the GeForce GTX 770 you get eight SMX units which results in 1'536 CUDA cores. Following the specs further, there are 128 TMUs, 32 ROPs, a 256 bit wide memory interface and 2 Gigabyte of GDDR5 memory, which is clocked at 7'000 MHz. In the end there is a memory bandwidth of 224.4 Gigabyte per second. Concerning the GPU's clock speeds it runs at a base clock of 1'150 MHz and a boost clock of 1'202 MHz. During our tests the highest boost clock we measured was 1'228 MHz, which happened to be the average boost clock too. In other words under load the GPU was always running at 1'228 MHz.

The GTX 770 also supports GPU Boost 2.0. The very first version of GPU Boost stopped overclocking the GPU when a certain power target was hit. This new, second version of GPU Boost stops overclocking the card, when a certain temperature is being reached. This makes sense since the temperature is the bigger inhibitor than the power target in most cases. In this case the temperature target is 80 degrees Celsius. In other words, as long as the GPU runs below 80°C it will keep overclocking until the maximum frequency has been reached. This is why in our case the average boost clock was 26 MHz higher than the typical boost clock the manufacturer advertises, the card never was near the target temp.

nVidia GeForce	MSI Lightning	ASUS DCU 2 OC	GeForce GTX 770	GeForce GTX 680
Chip	GK104-425-A2	GK104-425-A2	GK104-425-A2	GK104
Process	28 nm	28 nm	28 nm	28 nm
Transistors	3.54 billion	3.54 billion	3.54 billion	3.54 billion
GPU clock	1'150 MHz	1'059 MHz	1'046 MHz	1'006 MHz
GPU Boost clock	1'202 MHz	1'111 MHz	1'085 MHz	1'059 MHz
Memory GDDR5	2'048 MB	2'048 MB	2'048 MB	2'048 MB
Memory clock	1'750 (7'000) MHz	1'750 (7'000) MHz	1'750 (7'000) MHz	1'500 (6'000) MHz
Memory interface	256 Bit	256 Bit	256 Bit	256 Bit
Memory bandwidth	224'400 MB/s	224'400 MB/s	224'400 MB/s	192'300 MB/s
TMUs	128	128	128	128
Shader Cores	1'536 (8 SMX)	1'536 (8 SMX)	1'536 (8 SMX)	1'536 (8 SMX)
ROPs	32	32	32	32
TDP	260 Watt	230 Watt	230 Watt	195 Watt
PCB Type	Custom Design	Custom Design	Reference Design	Reference Design
Lenght (PCB - Total)	28.2 - 29.3 cm	27.0 - 27.0 cm	26.7 - 26.7 cm	25.6 - 25.6 cm
Height (PCB - Total)	13.0 - 14.0 cm	xx.0 - xx.0 cm	11.0 - 11.0 cm	11.0 - 11.0 cm
Slots	2	2	2	2
Cooler	MSI Twin Frozr IV	ASUS Direct CU II	NVIDIA Reference	NVIDIA Reference
MSRP	$XXX	$XXX	$399	$499

MSI decided to equip its GeForce GTX 770 Lightning with the latest version IV of their famous Twin Frozr cooler. In this case you get three six millimeter, nickel-plated copper heatpipes, which are surrounded by two eight millimeter ones. The latter are in contact with the GPU through a nickel-plated copper base plate. This one, unfortunately, doesn't have a mirror finish. Soldered to the heatpipes you find the fin stack which is being provided with fresh air via two 100mm PWM DC brushless two ball bearing fans. Those are manufactured by Power Logic and carry the model number PLD00015B12H.



A closer look at the PCB shows that MSI equipped this card with a digital 12 phase PWM design. In this case, the GPU gets eight phases, twice as much as on the reference model. The memory can rely on three phases, which take the power directly from the 8-pin power connector. Compared to the reference analog 2-phase PCI-E shared power design, this is by far the better way to implement it. The remaining phase feeds the PLL.
This card also features an unlocked BIOS (LN2 BIOS) that can be selected via a DIP switch, located at the top end of the card. Switching to this BIOS will disable all protections such as ASP (Active Phase Switching), higher the OCP (Over Current Protection) from 380 to 800W and higher the TDP from 300 to 900W. There are also two heatsink plates that keeps the card safe and cools the memory chips as well as the MOSFETs.
Component wise, the Lightning complies with MSI's Military Class III Components standard. It doesn't mean you will find military/NASA class components on the PCB, otherwise the card would have been so expensive you couldn't afford it. Still you find top quality components such as Golden SSC (trio R17 1320), CopperMOS (IR 8304 ARJH 1234 & IR 8327 9SUF 1228), All Hi-c CAPs for GPU (470 3330M) and Dark Solid CAPs (FP5K 35Ao 271 16).
Apart from that the Lightning also features triple overvoltage for GPU, memory and PLL via AfterBurner and voltage read-out points for CPU, memory and PLL located at the right end of the PCB.

Checking the voltage regulation chips we find a digital multi-phase buck controller CHL8318 from CHiL for the GPU and a three-phase PWM controller uP1612Q for the memory.

The memory chips used are made by Samsung and carry the model number K4G20325FD-FC28. They are specified to run at 1'750 MHz (7'000 MHz effective).

Page 1 - Introduction	Page 12 - DIRT Showdown
Page 2 - Technical Data / Specifications	Page 13 - Far Cry 3
Page 3 - Preview & Delivery	Page 14 - Sleeping Dogs
Page 4 - Test Setup	Page 15 - The Elder Scrolls V: Skyrim
Page 5 - 3DMark Fire Strike	Page 16 - Metro: Last Light
Page 6 - Unigine Heaven 4.0	Page 17 - Power Consumption
Page 7 - BattleField 3	Page 18 - Fan Speed / Noise Level
Page 8 - Borderlands 2	Page 19 - Temps - Idle / FurMark / BF3
Page 9 - Bioshock Infinite	Page 20 - Performance/Price & Performance/Watt
Page 10 - Crysis 3	Page 21 - Conclusion
Page 11 - Call of Duty Black Ops 2