Sapphire AMD Radeon HD 6870 Overclocking Guide

[theboi808]

great video but i have a few questions. how do you know what to raise(voltage, memory, core clock)? how do you know how much you have to raise it? im have no idea how the whole overclocking idea works for gpu's. i only know how with cpu's. can someone explain to me an in depth tutorial on over clocking this card (sapphire 6870) w/trixx?

[amintha100]

@theboi808 its the same idea as OC the CPU. to get more performance out of the card.

so just like the CPU we have clock speed, memory speed(rap/FSB in cpu) and voltage.

all these high to extreme cards have some head room to overclock with out increasing the voltage. this is because the manufactures want to keep the card at low power usage and heat output. but that does not mean it is unsafe to OC. wll up to a certain point it is fine. this limit is set by many factors.

[amintha100]

@theboi808 (part 2) such as your cards cooling system, cards power delivery system, and even the case that you are using coz the ambient temp can affect the GPU temp.

interms of OCing.. you increase the clock and memory speed to a certain point and run stress test if it holds with out a problem then either you increase again or leave it there.

if crashes the increase the voltage by little increments. IT IS VERY IMPORTANT TO KEEP AN EYE ON THE TEMPERATURE.

[amintha100]

@theboi808 (part 3) eventually you will hit the physical limits of the card. then you are done. remember a 1Ghz/1000Mhz is a huge clock speed for any graphic card. and in this video the memory speed that is shown is the real speed. since it is GDD5 memory you have to multiply by 4 to get the effective speed. (there is a setting that will display the effective speed in Trixx)

that was long and possibly confusing(hope not) but that is it...

any Q's PM me and subscribe :P

Cheers :)

[theboi808]

@amintha100 okay now i have a better knowledge on how to over clock it. so to begin, i take the core clock and memory and raise it one notch each from the default settings until furmark cant handle it. if it cant handle then i can either up the voltage or turn it down a couple notches to make sure its safe and everything right?

[amintha100]

@theboi808 thats the idea,,, but don't go more than 1.25V from the original amount. and i think you should not change values while furmark is running coz it might take u to a crash but same setting applied with out furmark running might be safe. its ok to go up by 10-15 each time as appose to 1 by 1 :) have a blast trying to fry your GPU

[theboi808]

@amintha100 thanks dude

[amintha100]

@theboi808 its good to know that my video actually helped some one....

[theboi808]

@amintha100 haha. i bet it is

[OrganicMK]

I have the same card, but when I set the clock to 1000/1200 then it`s very unstable. What could be the cause? Different CPU, RAM?

[amintha100]

@OrganicMK did you bump up the Voltage? because 1000mhz is not a small OC...

[OrganicMK]

@amintha100 I have XFX 6870 Double Dissipation card and no matter what program I use I can`t change voltage...

[OrganicMK]

@amintha100 Also, as long as XFX doesn`t have it`s own overclocking software I have to use some third party like Afterburner and Trixx. Are there an other known programs for overclocking?

[amintha100]

@OrganicMK those two are the most well known ones.... for the afterburner i didnt get voltage control for my card either

[OrganicMK]

@amintha100 So I took Sapphire 6870 Vapor-X from my other PC and have maximum stable settings - 970/1180/1193. The score on "Benchmark Preset:1080" is - 1807.

[amintha100]

@OrganicMK ok.... that is good right?

[OrganicMK]

@amintha100 Better that nothing

[amintha100]

@OrganicMK you know when the OC is highly effective? when you are in the middle of the game when the bad guys are trying to kill you,,,, it helps to keep the Frame Rate above the not playable limit :)

[sabufinisher]

im new to OC and i have a the same card as yours but i want to ask does the voltage effect or not?

[amintha100]

@sabufinisher yes it does. voltage is like food for a person. some one can do some heavy work with out food for a while but eventually they will fail. so it is the same. if we are asking more from the GPU and Memory (OCing them) we need to feed them too. but be very careful when u are increasing the voltage. always first increase the clock speeds and then test it using a software like furmark or play the game u want. see if it feels right. if it fails or crashes increase the Voltage a bit.

[amintha100]

@sabufinisher remember u dont always have to increase voltage coz there is a little bit head room before u hit point where u have to increase the voltage to get the card to stabelize

[teras231]

Can you run bf3 max or ultra with those settings?

[amintha100]

@teras231 yes i am doing ultra with full AA @ 1680x1050 with 45+ FPS

[airsoftrulzpaintball]

This is weird i overclocked my sapphire 6870 to 1ghz core and 4400mhz memory using 1.195v and i never go over 73c in furmark...

[revengeofMCR]

i have a XFX hd6870 and my voltage is locked

how to unlock?

[amintha100]

@revengeofMCR what is the program that u are using to overclock?

i used afterburner on my HD6870(just to see what happens) and i didnt have control over the voltage. but when i use trixx i got it. so i recommend using trixx

[revengeofMCR]

@amintha100 i used trixx and still without voltage control my GPU is XFX H6870 Double dissipation help me please

[lendial]

would skyrim benefit at all from gpu oc?

[amintha100]

@lendial well that depends on your system. i have never played skyrim or any in that that series. lets say that you are playing the game in full resolution and full details and the FPS count droops below 30 when you are playing the game... then you should think about OC a bit.... but if the game is heavy on CPU power like NFS shift 2 then OC the gpu dosent make a difference. because the bottleneck is the cpu not the gpu. hope this helped

[lendial]

@amintha100 i tried to oc but only got 1 fps gain even at 975/1125 so i just went back to stock clocks.

[amintha100]

@lendial ok.... i think that u are talking about when playing skyrim....so try another game and see if it increases plus 975 is not a significant increase, coz i think my stock speeds were 950.

[DaSurot]

wtf why is mine says in clocks 900/4200 mhz (core clock 900 / memory clock 4200) thats what trixx tells my default is. When I check on AMD control center its 1050 memory clock... the hell is wrong with my trixx

[azarobi]

@DaSurot There is nothing abnormal here. 900Mhz is your GPUs real memory speed. Depending on the type of the memory (GDDR3 or GDDR5) you have to multiply the real memory speed rate with a multiplier. for DDR3 memory the multiplier is 2. in case of DDR5, the multiplier is 4. You have DDR5 in all of 6XXX series.Hence 1050 x 4 = 4200MHz. This is also known as 'effective' speed. some software's show real speed while other go for effective. Its all same in the end. Cheers.

[amintha100]

@azarobi that is a very good explanation.

[azarobi]

@amintha100 Thanks man :)

[charlesbego]

6870 reference 900/1050

6870 oc version 940/1100

I overclocked my reference 6870 to 940/1100 with amd overdrive and it's running perfect.

But I changed it back to default clock.. no point to overclock it.. so little fps boost

[amintha100]

@charlesbego you have to play the game title that actually uses that extra boost to see it.. for example BattleField 3 at all the max settings...

[RoflCoptr20]

Nice, i have the same card i bought from newegg but whered you get the TRIXX utility from....im overclocking with MSI afterburner and my card is only stable up to 960/1200mhz on stock voltage if i try to go over those speeds then I get the display driver has crashed and recovered message. is that normal?

[RoflCoptr20]

@RoflCoptr20 oh and im running Catalyst 11.11 drivers

[80Loke]

@RoflCoptr20 i think u run the memory to high..1170mhz is where u want to be

[RoflCoptr20]

@80Loke Ya i usually run at stock speeds unless i need more then il run it at 950/1150, runs BF3 on ultra with 2xaa and af on max easy with those speeds.

[amintha100]

@RoflCoptr20 from what i remember i think i downloaded trixx program. just search it online.

[RoflCoptr20]

@amintha100 il probably just stick with MSI afterburner since it does the same thing, do you know if increasing the voltage voids the warranty?

[amintha100]

@RoflCoptr20 no i dont think so... and sorry for the late reply