kur¡,
Go here.
Look for "VDDC measure" in the pic...
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kur¡,
Go here.
Look for "VDDC measure" in the pic...
Hi, at last I've voltmoded my 4870. Thirst of all GPU OC potential strictly depends on Memory clock. Here are some interesting results I've got:
1.283v (default), possible variants:
(GPU-MEM 3DMark Vantage GPU Score)
875-1200 9976
1.300v, possible variants:
880-1200 10005
1.305v, possible variants:
890-1150 10099
880-1200 10007
1.325v, possible variants:
895-1000 9839
890-1050 9983
885-1100 10015
875-1200 9976
1.350v, possible variants:
910-900 9827
905-1000 9967
895-1050 10004
885-1100 10020
880-1150 9998
870-1200 9914
What does it looks like? Right, it's no other then over current protection and 90% that it's located in BIOS (by the way you can check current in gpu-z 0.2.7). So here's Power Play II AMD has been talking about. Well AMD did a good job on failing our OC. :D
I hope in future versions of RBE we could heal this anti OC protection. Until it's done, no WR on this adapter would be possible. :/
By the way, it was certainly not because of the over hitting (using 1.35V):
http://images.people.overclockers.ru/preview/163056.jpg
Could that be what causes my problem which is as followed:
My Powercolor 4870 is under water with the new EK FC block. Before vGPU mod I ran it at 850/1000.
Today I did the vGPU mod, and where ATI Tool would artifact above 850 before, I was now able to run ATI tool artifact free at 940MHz. (See picture).
My problem is, that eventhough ATI tool runs flawless, no game will run for more than a few secounds. Everything above aprox 1.37v will make the screen go black or the displaydriver to stop working.
It dosent matter if I only uses the same 850mhz as I did before the mod.
Lowering mem speed dosent do anything for me either..
Would it make any sense to try another BIOS?
Really hope you guys are able to help me out here :shrug:
http://www.solveig-iver.dk/jakob/Capture.JPG
Søndergård
How far does your adapter go with furemark?
Furmark gave me the :shocked: after a few sec.Quote:
Originally Posted by Dirton
^ Yeah, that's the same thing I got as I turned up the volts. Does your D601 diagnostic LED ever turn on when stuff crashes? I got it to turn on from time to time, indicated "critical core power failure". Only happens if you set voltages higher than 1.35V-1.37V on idle. It was very strange behavior indeed. I noticed that at this point VRM temps are also extremely high. Either way, it will not really matter what your clocks are in this case. The card will crash no matter what. If you lower the volts you will be fine. It must be that some OCP or OVP thing is kicking in...
Quote:
Originally Posted by dejanh
I think you just saved my day :D I tryed lowering the voltage to 1.35 and now Furmark dosent crash imidiatly. I was not ablo to run 900MHz core at that voltage, but at 1.375 I am running Furmark at 900Mhz. So far 5 min..
Now I just need to make some finer adjustments and find out how high I can go without the "problem" is kicking in.
Thanks again.
^ No worries. Glad I could help. :D
Which brand is your card (e.g., HIS, PowerColor, Diamond, Sapphire)?
Also, are you able to run the memory at least 1100 at that core speed? I found that the highest stable I could achieve with the Diamond 4870 XOC BE on air was 875/1125 at 1.358V core, 1.501V memory and 850/1150 at slightly different voltages. Either way, I did not notice almost any performance gain when compared to say 825/1125...
Thanks :)Quote:
Originally Posted by largon
Quote:
Originally Posted by dejanh
Well I have been using the Diamond 4870 XOC BE and ASUS TOP BIOS. No real difference here..
Hmm, the 900MHz core I can't get stable. I can get Furmark stable but then Crysis will fail, or the opposit.
Looks like the best possible all stable is about 880mhz.
The mem I havent messed with yet. Stock/water is only accepts about 1025, but I am considering modding the mem as well.
Quite dissapointet that the vmod only gave me about 30 Mhz from the non mod 850mhz oc I had before :( Though I am quite sure it is possible to bench much higher, as I was able to run ati tool artifact free at 940Mhz.. Maybe not..
Is my problem normal or? Is it possible that a mod will remove the OVP (If thats what causing my problem?)
What do you cool your card with? And how musk can I expect to gain in mem mhz when max stock is about 1025? (Know its hard to predict, but if it is just 25Mhz, I wont even bother). To me 24/7 and stability is nr.1
My cooling is a HR-03GT with a 92mm fan on top with stock HR-03 sinks on memory and VRM. I am looking to install this guy http://www.thermalright.com/new_a_pa...50aHVzaWFzdA== (an HR-09 Type 4) onto the VRMs. I already tried the HR-09 Type 2 but its wider 15.5mm base is too wide and cannot fit properly onto the VRMs. The Type 4 guy has a 12mm wide base so it should fit. I found that the card is extremely sensitive to upping the voltage on the core and the memory. When you do both you get BS much faster. I think in this case it is some kind of OCP kicking in. You will see that yourself if you try to voltmod the memory in addition to the core. With such a high core at 880MHz or 900MHz you will not be able to OC the memory much from your 1000MHz, or at all. I would say that you will get artifacts as soon as you hit over 1050MHz so if 50MHz is worth it for you to mod things go ahead. Unfortunately the 4870 XOC BE does not OC that well. I am not sure about other cards but I think most 4870 have a problem getting over 850MHz core and about 1125MHz - 1150MHz memory.Quote:
Originally Posted by Søndergård
I also found the same thing you did in terms of ATITool/FurMark and games. If I stabilize ATITool can be artifact free with high voltage at high core clocks with good cooling. However, FurMark crashes at those voltages so it forces you to go with lower voltages if you want higher clocks for FurMark. These higher clocks at lower voltages however cause instability in games as your lower volts now are not sufficient for stable operation in games so you need to lower your clocks as well. It is a really stupid cycle that I found. Hence the reason why I had to stabilize at the clocks I mentioned before. I have worked on this card for > 12 days straight with constantly the same results using three different cooling systems and several cards. All were with same results.
To summarize, what you will find is that if you up the memory voltage and memory clock you will have to lower your core clock and potentially core voltage, and vice versa. The highest stable overall combination will be something in between 850/1150 and 875/1125 (notice the trade-off between core and memory clocks :p:). Ironically, I found that in games the best performance was at 825/1125 clocks and that anything higher did not yield anything significant in terms of FPS (some higher clocks even yield less :rolleyes:) as well as that the performance at higher clocks did not justify the added heat output and power consumption of the board.
Edit: One other thing to note is that the Qimonda memory chips are 40X, so they are rated for max 4000MHz with critical maximum voltage being 2.0V (stock is 1.501V). Running them at 4400MHz or higher is already 10%+ OC on the memory so it is not that strange that it would be causing problem when trying to push it very high. Some people can run very high since they do not care about 100% stability and they do not even notice some artifacts in games so for them going 4600MHz - 4800MHz with high core clocks (> 850MHz) is okay.
Edit 2: I would not hold my breath on the OVP/OCP being disabled in the future using any BIOS or other hard-mod method really. I found in the past that there is usually just too much work involved in doing this with mixed results at the end. If anything, it severely increases your risk of blowing up the board.
Well, hmm I think I will sleep on it. But I guess I will remove the hardmod and flash back to 850/1000 with std. voltage on everything.Quote:
Originally Posted by dejanh
No regreds though, it was my first hardmod, and it was fun as hell! Now I am just hoping I can remove the solderings and keep my waranty intact.
:shrug:
Use a solder wick and it comes of like a charm :p: I did that already a bunch of times. Then after you are done clean the board with some alcohol or (my favorite) acetone :DQuote:
Originally Posted by Søndergård
How do you guys solder? Do you place the tinned wire to the pad/leg and then heat the wire? Or do you heat the pad and the wire at the same time? I know I want to avoid cold joints, but I don't think I can hit the pad and the wire at the same time. When I solder, it seems that the tip of the tinned wire becomes like the iron and heats the solder on the pad well.
Sorry, I'm new to this and trying to avoid failure. I've been practicing a lot though. This is hella fun!
BTW I'm trying to mod my 4850's.
Im only a beginner, but I put a small amount of solder on the tip og the wire. Then I touch both the solderingpoint and the wire until they mix.Quote:
Originally Posted by Rickpatbrown
So, what are you guys final results with the MVDDC og MVDDQ mods? What did they before and after, and what amount af voltage do you think I can use for 24/7 on water?
Stock volts on MVDDC/Q are 1.501V. If you OC, the maximum voltage tolerance for the Qimonda chips is 2.00V. They will fail at this voltage however if ran constantly. Because of the issues with OCP/OVP however you will not be able to run the core and memory volts very high together. Expect that if your core voltage is set anywhere between 1.35V - 1.37V you will not be able to get more than 1.65V to the memory without starting to experience the same issues as you did before. I'd say your most stable voltages will be about 1.37V core and about 1.6V memory.
I am personally finding that 4870s are proving to be very finicky for OCing.
The memory controller (obviously inside the core) will start to crap out when using too high core speed & voltage. At core 850MHz @ 1.350-1.375V (whatever I used) it becomes really fluky and my card (HD4850) will no longer pass FurMark stability test. 1.400V core doesn't help, neither does 1.450V, neither does 1.500V . :shrug:
However the card is perfectly bench & game stable in other bench app's & games. Now the question is;
How smart is it to squeeze the core for the last 50MHz when the card & its performance is already held back by the "low" clocked GDDR3 mem?
These will not run safely beyond 1200-1250MHz.
How smart is it to create an even bigger memory bottleneck? :shakes:
However, getting the core speed up to max on the HD4870 is a different story. The GDDR5 memory allows this card to scale properly with core speed up to at least 1000MHz (I'd think). :yepp:
//
I don't know, but I think I'll keep my HD4850 at ~800MHz core, 1150MHz mem (give or take 50MHz on both! :D).
Hi guys , I just ran some tests on my new 4870x2 and fitted a 4870 for tri-fire but my pc will not boot with the 4870 installed , I get cmos error code shown on the lcd poster , has anyone else seen anything like this ? I have had this vid card in this pc before , and the pc will boot with either vid card on its own.
This vid card has been flashed with the modded bios , could this be upsetting things ? Or would they just dislike cf if that was the case ?
Any help would be greatly appreciated.
:up:
you don't mention what kind of power supply you have.Quote:
Originally Posted by aussie-revhead
This is only in theory. In practice there is no way that you will come even close to 1GHz core. 900MHz stable would be very lucky. Granted, one thing is true, the added mem bandwidth does kind of push one to try to push the core as high as possible.Quote:
Originally Posted by OnLine
I was just re-reading something and I noticed this...
You are saying you are not failing due to over heating at 1.35V, but you are running your GPU at 1.263V which is the default voltage (not 1.283V). Try actually running FurMark with 1.35V and high clocks. Otherwise, good observations, there is a definite link between maximum core and maximum memory :)Quote:
Originally Posted by Dirton
Someone made a pencil vmod for the 4870?
no, its not possible. there is not resistor to pencilQuote:
Originally Posted by MonsterMash
God damn'it, so the only way to make a vmod on a 4870 is soldering a vr?Quote:
Originally Posted by SNiiPE_DoGG
yes. for that matter it is a fairly easy voltmod the vddc point is very isolated. if your not good at soldering its hard though because the point is very smallQuote:
Originally Posted by MonsterMash