GeForce 7800 GTX 512MB (SLI)

Graphics cards 1048 Page 2 of 3 Published by

teaser

Page 2 - Into the heart of the beast

Entering the heart of Mordor

G70. You must have heard about it as it is the same chip used on the GeForce 7800 GTX 256 MB. It's NVIDIA's internal codename for the graphics core. G70 is thus a synonym for the graphics chip used on the GeForce 7800 GTX. At this very moment, this is the second model released in the 7x00 range with now two products. I'm not doubting there will be many new products later on. The 7800 GTX is a tiger yet the new 512 MB version is the king of the jungle, the new flagship, the fastest available ... Neo, is that you ?

Let's do some sexy tech talk. The number of transistors versus fabrication size in the actual silicon gives us a nice idea about performance.  Intel's new Pentium 4 6xx series for example have 169 million transistors. The GeForce 6800 already had 222 million transistors. The GeForce 7800 GTX cards have 302 million transistors, crazy huh? It's being manufactured on a 0.11 micron fabrication process. Let's have a peek at the Series 6 and 7 products from NVIDIA but more importantly their technical differences.

NVIDIA GeForce 6 & 7 Product Lineup Specifications

Product Name

# pixel processors

# vertex processors

Bus width

Memory Type/Amount

GPU Speed

RAM Speed

GeForce 7800 GTX 24 8 256-bit GDDR3/512MB 550MHz (850) 1700 MHz GeForce 7800 GTX 24 8 256-bit GDDR3/256MB 430MHz 1200MHzGeForce 7800 GT 20 7 256-bit GDDR3/256MB 400MHz 1000MHz

GeForce 6800 Ultra **

16

6

256-bit

GDDR3/256MB

400MHz

1100MHz

GeForce 6800 GT

16

6

256-bit

GDDR3/256MB

350MHz

1000MHz

GeForce 6800 GS 12 5 256-bit GDDR3/128/256MB 425MHz 1000MHz

GeForce 6800

12

5

256-bit

GDDR/128MB

325MHz

700MHz

GeForce 6800 LE

8

4

256-bit

GDDR/128MB

320MHz

700MHz

GeForce 6600 GT 8 3 128-bit GDDR3/128/256MB 500MHz 1000MHzGeForce 6600 8 3 128-bit GDDR/128MB 300MHz 275(550) GeForce 6200 4 3 64/128-bit GDDR/128MB/256MB 300MHz 275(550)

** Not manufactured anymore

Overall, the 7800 GTX (Series 7) is mostly about increased efficiency and higher performance over the previous generations products. Normally we see little steps up in performance, yet with 24 pipes, 8 vertex units and a huge transistor count combined with some nice internal hardware optimizations, the boost in performance is noticeable, especially on the new 512MB version. I have no clue why it was not labeled "Ultra".

  • 256-bit GeForce 7800 GTX 512 MB (550 MHz clock)
  • 302 Million transistors
  • 8 Vertex Shading Units
  • 24 Pixel pipelines
  • 512 MB 256-bit 1.2ns (8x32) GDDR3 Memory (850MHz clock - 1.7 GHz effective)
  • PCI Express x16 Compatibility (PCI Express Compliant)
  • Integrated NVIDIA TV Encoder (HDTV, S-Video, Composite,)
  • Integrated NVIDIA VIVO (S-Video, Composite,)
  • Dual DVI-I Connectors
  • 54.4 GB per second memory bandwidth
  • NVIDIA PureVideo Technology
  • DVD + HDTV Decode assist up to 1920x1080p resolution
  • Integrated Dual 400MHz RAMDACs
  • 1 Dual Link TMDS DVI Connector
  • 1 Single Link TMDS DVI Connector
  • NVIDIA Digital Vibrance Control (DVC) 3.0
  • Support for Microsoft Video Mixer Renderer (VMR)
  • Advanced adaptive de-interlacing

What you likely want to know is what the technical differences are between the the "regular" 256 MB version and the "new" 512 MB version of the GTX. Basically, two things. The 256 MB GTX had it's graphics core clocked at 430 MHz and it's memory at 600 MHz (1200 effective). The new 512 MB GTX has a core clock of 550 MHZ and it's memory at 850 MHz (1700 effective). That is a HUGE bump in core performance and framebuffer bandwidth. That framebuffer bandwidth (framebuffer by the way is the local memory on the graphics card) was at an already fast 38.4 GB/sec and now is at 54.4 GB/sec.

An interesting fact is that the memory onboard is actually rated 900 MHz. So on purpose NVIDIA left you some overclocking abilities. This memory can run at 1800 MHz without any issues, guarranteed.

Specs GeForce 6600 GeForce 6600 GT GeForce 6800 GeForce 6800 GS GeForce 6800 GT GeForce 6800 Ultra GeForce 7800 GT GeForce 7800 GTX GeForce 7800 GTX 512
Codename NV43 NV43 NV42 NV42 NV40GT NV40U G70 G70 G70
Transistors ? ? 222 million 302 million 302 million 302 million
Process, GPU maker 110nm 110nm 130nm 110nm 130nm 110nm 110nm 110nm
Core clock 300 MHz 500 MHz Up to 400 MHz 425 350MHz 400MHz 400 MHz 430 MHz 550 MHz
Memory 128MB DDR1 128MB GDDR3 128MB DDR1 128/256MB gDDR3 256MB GDDR3 512MB GDDR3
Memory bus 128-bit 256-bit
Memory clock Up to manufacturer 2x500 MHz 2 x 325MHz 2x
500MHz
2 x 500MHz 2 x 600MHz 2 x 500MHz 2 x 600MHz 2 x 850MHz
PCB P212 P212 P2?? P210 P210 -
Pipelines 8 8 12 16 16 20 24
FP operations FP16, FP32
DirectX DirectX 9.0c
Pixel shaders Pixel Shaders 3.0
Vertex shaders Vertex Shaders 3.0
OpenGL 1.5+ (2.0) 2.0
Availability Now

Share this content
Twitter Facebook Reddit WhatsApp Email Print