Bitcoin Forum

Hi Again!, Well, It looks Like I'm On The Hunt For A New GPU ;D I saw A Radeon 7870 at An SA Online Store (http://evetech.co.za) for about 2700 ZAR.
That's Just over 260 USD - Well, I checked The Bitcoin Wiki, and all there Is Next To This Particular Card Is... ??? (No Info whatsoever) So If Any Fellow Miners :P Have any experience with this card... please Let Me Know(Mhash/s etc) Thanks.

A 7970 gets ~550MH/s @ 1000MHz with 2048 SPU

A 7870 only has 1280 SPU @ 1000MHz, so that equals about 343MH/s. You could prolly hit 400Mh/s if you OC'd a good bit.

Mining hardware comparison (https://en.bitcoin.it/wiki/Mining_hardware_comparison)

so a 5870 (@930 i get 420Mh/s) it`s still better that 7870... damn!

Those 5xxx series cards were amazing for mining. IIRC, the architecture was almost perfect for mining. Even a 6970 can barely get over 400MH/s.

The main performance gains of the 7970 (anywhere from 550-700MH/s) was from the lower die size (28nm), which means more cores at lower power and less heat.

My 6970 was getting 430Mhash/s @ 960MHz / 150MHz and now I'm getting 440MHash with 1000MHz/300MHz 5870

-fankih-

I picked up 2 Diamond Black Overclocked 7870s and bumped the voltage to 1.25v and was able to get about 440 MH/s out of each one stably.  They are using significantly more power than stock - but they're decent for density.

Overvolting is typically a bad idea, as your VRM temps will be extra hot 24/7. Unless you're watercooling, watch those VRM temps.

And 440MH/s is about what my 5970 did on stock volts. So again, not really a huge improvement.

I run a 7870 right now. It runs about 240W @ 395mhash/sec. A tiny bit of overclocking and I run about 425mhash/sec.

Thanks For All The Replies! However... I just Pre-Ordered My 3-Ghash/s Asic Device From Butterfly Labs! I Hope It Was A "Wise"
Investment... Thanks again anyway. (Can't wait until October!)

October of which year?

A 7970 gets 597MH/s @ 1000MHz with 2048 SPU

Not cards are identical..... Jim's 7970 might get 550mh/s and Dick's 7950 might get closer to 600mh/s @ the same clock speeds.....



I have a few identical 5800 series cards that don't mine exactly the same.....

No, he's right. I was thinking of a 7970 getting ~550MH/s @ the stock 925MHz. 1000MHz does give just under 600Mh/s.

Just got a sapphire HD7870 OC version.

First thing i noticed ASIC quality of 85.2%,which is pretty good in my book.Also default voltage shown was 1.164 instead of standard 1.208.

The sweetspot seems to be 1100@1.056V,multimeter and vddc reads 1.006,temps are 65C@stock cooling,vrm is steady at 75 degrees C,lowered a bit the fan so basically the card is DEAD silent.

Currently i get 405Mhash/s @1100.Will try new clocks next days.I think i got a pretty decent clocking card.  ;D

http://img29.imageshack.us/img29/5861/7870mining.jpg

That looks pretty good! I always love an overclock that goes with an undervolt  ;D

What's your power draw at the wall?

I don't know honestly,but the other components are an i3 2100 undervolted to 1.00V  ;D a SSD and some low-voltage ddr3 ram at 1.35V.My power supply is a seasonic x-650 at it;s fan does not spin most of the time,so i guess the whole package is around 200w from the wall.

0% stale? I'd like to know what pool you're mining at please.

Added to the Mining hardware comparison (https://en.bitcoin.it/wiki/Mining_hardware_comparison).

I have two Gigabyte 7870s OC'ed to 1175 with 1231 voltage in afterburner and they get 435 m/hash 24/7.

running them in a corsair 400r case and temps are about 74/63 (ambient 25).

Switched to diablominer,got 413MHASH@1100 core,7-8 better than poclbm.Not bad...