The fermi architecture was reavealed by Nvidia way back in 2009 and the first Nvidia GPU series to be based on that architecture was the GTX 4XX series.The first card to be released was the GTX 480,and later on various other cards were released.Then the GTX 5XX series was released not too long ago with the first card being the GTX 580.
Major differences Between previous gen GPU’s like GTX 2XX and the new fermi architecture are as follows :
- Fermi based cards have GDDR5 memory modules with ECC(Error Correction) capabilities while the older architectures had GDDR3 non ECC modules.
- Fermi based cards had core clock and shader clock speeds interlocked in the ratio 1:2 while the older architectures need not be so.
- Fermi based cards were the first ones to support OpenGL4 and DirectX11 API’S(Application Programming Interface).
- Fermi based cards had tessellation units specifically for its hardware based implementation while the older architectures lacked it.
Well there are many more differences but for the sake of simplicity these are the most important ones to be concerned about.
List of GPU’s based on the Fermi architecture:
- Dual GPU : GTX 590
- High End : GTX 580,GTX 480,GTX 570,GTX 470
- Mid End : GTX 560 TI,GTX 560,GTX 460,GTX 465,GTX 550 TI,GTS 450
- Low End : GT 545,GT 440,GT 530,GT 430,GT 520,GT 510
Setting Up Your System :
- Firstly no BIOS adjustments required for the GPU OC unless you have changed your PCI bus frequency,if yes then change the PCI frequency to default.
- Now login to windows and install some essential Softwares/Utilities(Discussed later on in the next section).
- Now set all your card Frequencies to default/stock.
1) Geforce GPU Drivers–Do we need an explanation here .
2) MSI Afterburner–“The” best and “The” most user friendly OC’ing app available on earth.
3)Unigine Heaven–A very good benchmark for DX11 Tessellation enabled GPU’s.
4)OCCT–A gem among stress testing apps,a very versatile GPU testing/stressing Tool.
5) 3DMark11–A very Good DX11 GPU/CPU stresser.
6) GPU-Z–GPU monitoring Tool.
Understanding Some Basic Stuff :
Memory Frequency/Clock : This is the speed at which the VRAM or the GPU’s RAM work,this is the least important frequency while OC’ing as it yields very very less gains in terms of performance.
GPU VCORE : Its the amount of volts fed into the GPU’s core,its the most Important voltage for OC’ing GPU’s.
Safe Limit : Stock – 1.1Volts
Mem Volt-Important for OC’ing memory.
PLL Volt-Its just a gimmick by the manufacturers ,till now there has been no evidence of the card being able to OC higher and be stable by increasing the PLL Voltage.
Some Basic Rules Before Moving On
- Don’t set a target in mind,OC’ing is a recursive process,there is no guarantee you will achieve your desired overclock.
- Make sure your GPU temps are within 85C before any overclock @ stock,because if your cards already above 85C at stock,there won’t be much overclock headroom available to you,it does not mean your card can’t overclock,but it means that its not too safe to run your GPU at 90-100C 24X7.
- Make sure your GPU is dust free as dust will add in to the temps of your GPU.
—–Without Messing With The Voltages
- 1) After booting into windows start GPU-Z and Afterburner,close any unnecessary applications,verify your cards stock clocks and voltage.Also update your GPU drivers.
- 2) Now to start OCing bring afterburner into view and you will see 4 sliders by defaults namely
- Core Clock
- Shader Clock
- Memory Clock
- Fan Speed
Here our aim will be to stabilize all the clocks one by one.We start with core clock(core and shader clocks are linked so essentially you will be increasing both automatically if you increase any one of those).
- 3) Start raising the core clock speed 10 MHz at a time(you can also increase more if you are feeling adventurous but increasing in lower steps ensure that you will find more stable and safer highest frequency).After each increment run 2 loops of unigine heaven and 3dmark vantage/11 benchmarks,as these will immediately show the stability of your GPU OC by either crashing/slowing down/texture corruption or any graphical anomalies.
- 4) Repeat the above step till you GPU OC passes all the tests without any problem,after you start getting problem reduce the core clock in increments of 5 MHz and again run 2 loops of unigine and 3dmark benchmarks each,and keep decrementing till your card becomes stable and stops artifacting or giving any problem.
- 5) Through the last step we have now successfully found out our stable and highest core clock ceiling.So now in a way we have isolated the core clock from memory clock as memory clock have been untouched till now.So now start incrementing memory clock in increments of 10 MHz(Please don’t be over adventurous with memory like with core clock,memory is the component which can be easily destroyed by the slightest of mistake).Now repeat the same benchmark runs and strategy followed for core clock in earlier steps and you would have found out your memory clock ceiling too.
- 6) Congratulations! you have achieved a stable OC on your GPU without messing with voltages.Now to keep these settings click “Apply Overclocking At Startup” in afterburner,and save the OC settings in a profile represented in afterburner as numbers at the bottom.
—–With Messing With The Voltages
- 1) Here we follow the above 6 steps word to word and follow up from there.Now that we have got stable OC without increasing voltages,and if we need even higher OC then we need to up the voltage in small increments.
- 2) Now for this we need to make some changes in the options of afterburner,click options in afterburner and then under the generals tab check the “unlock voltage and enable voltage monitoring options”.
- 3) After setting up afterburner increase the core clock by 10 MHz again and again benchmark it and see if it crashes,if it does increase the voltage in increments of 5 mV and then again benchmark and see if the card has stabilized or not.
- 4) Repeat the procedure given above till either you reach your desired OC or you reach 1.1 V.
- 5) Once you reach the max possible OC apart from running the benchmarks also run OCCT GPU test for at least 30 minutes and check the stability of the card,if it survives well you have achieved a successful Overclock,if it does not decrement the core clocks by 5 MHz and keep doing this till your GPU is stable.
- 6) Final step enjoy gaming with increased performance .