Post
Topic
Board Mining (Altcoins)
Re: Any word on amd vega hash rates?
by
dragonmike
on 19/12/2017, 15:54:13 UTC
I dont know how you got 1900h with only 925mhz on the memory.   GPU core sure doesnt matter as much but I find if I adjust memory speed at all it brings down the hash speed right away, I stay as close to 1105mhz as possible, anything below 1050mhz will definetly show.     
I do think its possible to run the top speeds even at 900mv if the temps are all below 70c.   I use a cold air intake from a window, its winter now so its not hard when temps are 5c outside ?


The latest AMD driver release  allows swapping of config files apparently, saved defaults for various protocols sounds possible.  However they dont switch to compute priority for every type of hashing, havent fully tried yet

Any UK users have got this and using the AMD VEGA cards?

Mind sharing the price and source to get them, I've been trying really hard to get the RX 580 from past 3 months but no luck, any help from UK users would be much appreciated.

Hope I get some answers, thanks.

You are a bit late to the party.  The best deals was on release.   We are in transition now hence the lack of stock.   I suggest you look at overclockers.co.uk and join the forums and look out for deals, not that I know of any forthcoming like I said

1100 core with 1025 memory, both at 875mV (set with wattman, or overdriventool) on blockchain driver definitely works on vega 64 with no mods , and yields over 1900 H/s at low consumption. And is stable.
So there is still room for exploration here.


Something's very weird. If I try 1100 core @ 875 and 950 hbm @ 900mV miner crashes after a few seconds. It's like the memory is hitting a wall above 930. Sad
Ok so I just realised the GPUs aren't taking the OverdriveNtool settings apart from fan speed and memory clock. Core clock does whatever the fvck they want and so do the voltages. HWinfo64 shows 1.25V on the memory despite me having set it at 900mV... Tongue I think I'm going to give Wattman a go Sad

Blockchain drivers dont support voltage adjustment. So it has to be done with softpp mod, overdriventool has a builtin editor for it. 2nd, hbm volts are offlimits, only way to mod it is to switch between v56 and v64 bios. V64 has 1.35 and v56 has 1.25v.
Thanks, that's a useful piece of info. The guides are good but I hadn't explicitely read about the fact the softpp mod was required to access voltages. I'll look into it in a bit more detail.

The hammer/blunt force approach to this is to go into wattman and increase the power draw slider for the card. Move it up a few percent to see if you don't feel like calculating new values for the reg. Its not precise enough I know but you can watch the watts at the wall.
What would this achieve though, other than sucking even more power?

Currently I have basically tried variations of these two main options (short of a bios mod):

1. 1407@905mV core and 925@900mV hbm (1900h/s/card - 1385W @ the wall for the 6-card rig)
2. core -20% tdp, 925@900mV hbm (1800h/s/card - 1125W @ the wall)

For case 1, HBM temp is between 75 and 82C
For case 2, HBM temp is between 60 and 70C

In either case I cannot increase hbm speed or the rig will crash.

Is a bios mod the only way to get higher speed? I read from other people clocking their Vega 56 HBM at close to 1100!... How on earth do they do that?

There is no way to clock V56 HBM to 1100 without V64 bios ie. with higher mem voltage. Seems like 950Mhz with v56 bios is about max and some cant do even 900mhz. Then again, higher than 1100Mhz is possible by increasing SOC clock with same softppmod method. Default is 1107Mhz so anything over that wont work without mod. Increasing SOC also means you need to use higher core voltage, some need over 950mv some 900. Im using softppmod set at 865mv, and would need a lot more to increase SOC, which would mean way too much heat and noise.
So the answer to get a faster, more efficient setup is really to flash the 64 bios.
No chance of getting higher HBM speeds nor a more efficient setup otherwise, as you couldn't offset the loss of hashpower due to lower TDP/core speed by higher mem speed.

Looks like I'm gonna play around with vbioses over the xmas holidays...

Which bios will people usually flash? The primary one (i.e. the default switch setting on the Vegas) or the secondary? Does it make a difference?