Unlocking GTX 465 — own research

After a short period when the card was announced there was found a way to unlock CUDA cores of GTX 465

Comment: 1

Download 465 Upgrade Tool

June 1st 2010 NVIDIA officially announced another Fermi architecture graphic card — GTX 465.

The new card has reduce to 352 number of CUDA cores while having 1024 Mb of memory:

GTX 465 GTX 470 GTX 480
GPU Engine Specs:
CUDA Cores 352 448 480
Texture blocks 44 56 60
Raster blocks (ROPs) 32 40 48
Graphics Clock (MHz) 607 607 700
Processor Clock (MHz) 1215 1215 1400
Texture Fill Rate (billion/sec) 26.7 34 42
Memory specs:
Memory clock (MHz) 1603 1674 1848
SDRAM type 1024 MB GDDR5 1280 MB GDDR5 1536 MB GDDR5
Memory Interface Width 256-bit 320-bit 384-bit
Memory Bandwidth (GB/sec) 102.6 133.9 177.4
Feature Support:
NVIDIA SLI®-ready yes
NVIDIA PureVideo® Technology yes
NVIDIA PhysX™-ready yes
NVIDIA CUDA™ Technology yes
Microsoft DirectX 11
OpenGL 3.2
Bus Support PCIe 2.0 x16
NVIDIA 3D Vision Ready yes
NVIDIA 3D Vision Surround Ready yes
Display Support:
Maximum Digital Resolution 2560×1600
Maximum VGA Resolution 2048×1536
Standard Display Connectors 2x Dual Link DVI, Mini HDMI
Multi Monitor yes
HDCP yes
HDMI yes
Audio Input for HDMI Internal
Standard Graphics Card Dimensions:
Height 4.376 inches (111 mm) 4.376 inches (111 mm)
Length 9.5 inches (241 mm) 10.5 inches (267 mm)
Width Dual-slot
Thermal and Power Specs:
Maximum GPU Temperature (in C) 105
Maximum Graphics Card Power (W) 200 225 250
Minimum Recommended System Power (W) 550 (minimum 38 А on a +12 V rail) 600 (minimum 42 А on +12 V rail)
Supplementary Power Connectors Two 6-pin 6-pin and 8-pin

A close inspection of both GTX 465 and GTX 470 revealed than GTX 465 differs only by having less memory chips, two, to be exact:

GTX 465 board

GTX 470 board

After a short period when the card was announced, Romanian colleagues had found a way to unlock CUDA cores of GTX 465 by flashing GTX 470 bios. After some modifications with GTX 465 bios, all 448 CUDA cores become available, which results in a significant performance growth. Chinese resource chiphell.com continued card modifications by trying to unlock GTX 465 the software way.
Our resource got lucky to obtain the software that unlocks CUDA cores of GTX 465:

GTX 465 unlocking tool

We could not test this tool since we had no appropriate graphic card, however, we did found out more about the tool itself.

GTX 465 Upgrade Tool consists of an executable file and NVFLASHWINDOWS 5.95 software. The executable itself has a digital ASUS signature — this means that this tool was created somewhere in headquarters of ASUS laboratories and is not a result of a work of some enthusiast guy. The main idea of the tool is:

  1. NVFLASH searches for the card with DEVICE ID 0x06C4 ( 465) identification number
  2. Read its BIOS, NVFLASH uses following key --filterdevid 0x06C4 -b Log.rom -A -s
  3. The main software replaces 4 bytes in BIOS. If you can intercept the patched LOG.rom and compare it in Hex-editor with the original BIOS, then you can see what bytes were changed
  4. Flashes modified BIOS back to the graphic card using this initialization line NVFLASH --filterdevid 0x06C4 --refreshstraps --overridesub --overrideboard --nopreserve --auto --noconfirm Log.rom -5 -6 -A

In fact, GTX 465 Upgrade Tool flashes GTX 465 with the bios from GTX 470.
Those four bytes that are modified in BIOS stand for the core number configuration of the card.
Therefore, it is not hard to determine BIOS area which is patched by the tool and its changes.
We decide to conduct our own experiment which should reveal the possibility to unlock CUDA cores of GTX 470 to reach the number GTX 480 has. The replacement of target data of GTX 470 BIOS with the configuration of 480 BIOS have not been successful — the number of available cores has not changed. Next we tried something risky — flashed GTX 470 GTX with the 480 BIOS. The card remain to be working, but still no success in core unlocking. From this we can conclude that core configuration of graphic cards based on GPU GF100 is determined not only by BIOS, but also by PCB elements. Most likely shorting some board’s contacts together with BIOS data determines that cherished core configuration.

We, on the other hand, make own conclusions based on the information on Internet about successful results of GTX 465 unlocking to have GTX 470 core configuration — the owners of these cards had all cores originally unlocked, however, the configuration was hidden by the BIOS.

To make final conclusions on possibilities to unlock GTX 465 we need sample of GTX 465 in our lab.

Thanks to:
Mo3ulla and Cotulla for analyzing the machine code and help in BIOS modification

Update

Full review GTX 465 with unlock

Ads by Google

Discussion

Leave a Reply

Zibri, January 15, 2011 at 6:04 pm

Zibri,

I’m sure this can be done on the GTX 460 too…