AOC - HD4870@1,1GHz GPU

[|ron]

Hi guys, we're currently working on this Sapphire HD4870, the goal was to set all the italian hw category records but I'm posting this because, even if it's an old VGA, it still gives us a lot of fun and because of the crazy GPU frequencies reached!

 

This is the screen, taken at the very last thermos of LN2 (the score could be improved by tweaking the OS, this is just a fresh installation with a crappy 2600K):

 

http://hwbot.org/community/submission/2149422_aoc_3dmark2001_se_radeon_hd_4870_112592_marks

 

As you can see on hwbot, 1,1GHz GPU is something that only hipro, pofigist and m4nol reached, wow!

We did a run even at 1110MHz, but the score decreased due probably to high temps or low voltage (1,6v idle, 1,64v full), but we had no more LN2 to improve it.

I hope to be back soon with some 115k+ 01 runs, this VGA deserves it!

[TaPaKaH]

1100 on RV770 is not an extremely difficult achievement, there are lots of people who did that with 4850 ... not sure if it's harder with 4870, but still a nice freq

[|ron]

Hi Sam, given that there are only 3 people at 1100mhz in 4870 category and 13 for the 4850s, I think that the complexity resides in Gddr5 management for the GPU or to be more precise, for the MC inside the GPU.

In fact, in our early session (it was like 2 years ago, prior to put this vga in the shelf to dedicate to other stuff ), we couldn't reach more than 1030mhz.

2 weeks ago we completed the vmods by doing VDDQ and Vdimm.

I think that Vddq is the key: by having it at a higher voltage than stock, it gave to the GPU the extra stability needed to go up to 1,1GHz

 

2 pics of the card in action:

 

[Massman]

The biggest problem with the card is the OCP on GPU side, no?

 

1100 for the 4870's is pretty good. They were replaced by 4890 and only in the second gen 4890's there were pcb designs that could take high clocks easily.

[K404]

112.5K at only 5.1GHz.... really nice!

[|ron]

No OCP till now Don't ask me why, I used high voltages and frequencies so I thought that soon I would be blocked by OVP/OCP but... nothing.

Yeah, on the 4890s you can go very high with the freqs, we have a 4890 Vapor-X that can do 1080+MHz on air, really impossible for 4870s.

 

This is our non-reference blue PCB:

 

Those crappy chokes are BOILING!

 

@K404: thanks! We MUST find another 5,6+GHz 2600K

[bob80]

Hi Iron the clock you reached on the gpu is pretty good, good work

I'm sure that when you will find a good 2600k you'll improve all the benchmarks results and take the wr

 

BRAVO

[|ron]

Hi bob, it'll be a though task to beat RedCobra, GHZ and Kal-El scores, but at least we'll try

120K is an awesome score

[|ron]

Update here:

As I said, we just did another run with the 4870 with a better cpu, the goal was to set the new category WR, but we couldn't beat RedCobra's score of 121.527!

Anyway, we reached 2nd spot, with the vga now@1110/1100!

http://hwbot.org/community/submission/2159077_aoc_3dmark2001_se_radeon_hd_4870_120408_marks

 

 

RedCobra said he's going to put his 4870@ln2, so it would be interesting to find out what he'll manage to get!

We absolutely need a cpu like the one he has (approx. 150mhz better than ours).

[Splave]

nice card! mine shuts down at 1.5v powercolor PCS+ 4870

[|ron]

Ehi mate, how about doing an ocp mod? Nobody vmodded a 4870 with your pcb?

 

p.s.: what is this, Panda Invasion?

[|ron]

Tonight we did our last run with the 4870 and finally came the WR at 3DM01!!

We met with Coolbits, we brought his CPU and togheter we worked out this 124,4K!

As you can see from the frequencies, the card is almost degraded, probably the chokes are gone.

So there was plenty of room for improvement but the time was little so we didn't manage to pass the 125K mark, but we're happy as well.

Here is the screen:

 

Finally a run at Aqua, bad efficiency, but the strange fact is that the VGA performs better, speaking about max frequencies... probably it's because Aqua is lighter that 3DM01.

[Turrican]

congratz, nice scores.

[|ron]

Ehi thanks Turrican