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Nice clocks!Quote:
Originally Posted by bubu..
What kind of cooling are you running on the mem, just heat sinks?
I'm running 2.2Vmem, but I wouldn't mind giving 2.3 a shot myself...
What is the maximum Vmem for these chips?
Wow 1.4v, is that your 7900?? My ICs were hot...but not that hot! Glad I've got heatsinks and good airflow on them now in any case
1.4v,
Is that your card with the melted IC? If so what kind of voltage were you putting through your card (GPU/MEM)? That pretty hardcore, sorry to see your card got burnt, and welcome to the forum!
:)i meet the same problem with you. it's caused by the OC of memory speed. it appears when memory is running at 930, but all is good when it back to 920. try to decrease your memory speed to see what would happen.Quote:
Originally Posted by iRoNeTiK
God. which mod have you done? just v1.4?Quote:
Originally Posted by 1.4v
I did the 1.4v on my bfg 7900gt, here's my results .. got 5700 on 3dmark 06, compared to about a 5200 on stock ( i think it was)
it seems if i go any higher over 645, when i run 3dmark06, it will freeze ocassionaly for about 15- 20 seconds on the gpu test and my score will be really low.... strange thing is there is no artifacts though ...
you guys think i need to up the voltage in the bios maybe? or what:confused:
bwt my temps are 46 idle, around 60 load with the vf900
http://i54.photobucket.com/albums/g8...rs/goodbfg.png
Looks like you shorted out the pins when you installed the heatsink, did you "accidentally" touch the pins whilst installing with the card running ??Quote:
Originally Posted by 1.4v
Very sorry to see anyway, maybe you can source another similar IC and do a swap over if you can solder OK as long as other components were'nt cooked as well
i think im having the issue u posted on the consolidated 7900gt sticky about the switching frequency..i kept my ram @ stock which is 750 so 1500 and it doesnt matter, forgot to add that in. So i think i need to do the pencil mod to lower the resistance on that "k" resistor?Quote:
Originally Posted by taotao0210
Also I have sinks on my ram right now but i want to put the same sized ones on those two IC's but where can i get some for cheap? everyone has these copper ones for like 20-30 dollars for a pack but i only need 2 :)
That is a good point alphaOne, if that is the only IC that was heavily damaged it could be fixed. Forutnelty that particular IC has large pins and only 8 of them, I feel confident that I could pull that one off and replace and solder a new one in it's place (and I'm no expert by any stretch)! It would be worth a try 1.4v, you have nothing to loose, can't get worse than that!Quote:
Originally Posted by alpha0ne
That is a good point alphaOne, if that is the only IC that was heavily damaged it could be fixed. Forutnelty that particular IC has large pins and only 8 of them, I feel confident that I could pull that one off and replace and solder a new one in it's place (and I'm no expert by any stretch)! It would be worth a try 1.4v, you have nothing to loose, can't get worse than that!Quote:
Originally Posted by alpha0ne
what memory speed have you gotten now with v1.5 mod? i think you can do pencil mod to menory if you have a good air flow.Quote:
Originally Posted by iRoNeTiK
sorry for i can't tell you where to buy the sinks for those IC because i am in china :) i got them form a machine factory, there are lots of wast metal can be used to to this.
My card isnt the best but I haven't touched the memory really. I been up to 670 core but I need to do that switching frequency mod 1st to fix the problem and then ill do the pencil memory mod and let you know. Weekend is here, time to play hehe.
What is a good strategy/method of applying the lead to the resistor? Seems like a stupid question, take lead and start to cover resistor with it? lol just wondering if there are any good tips while doing it to make it easier on myself.
write a line (shade resistor a bit), measure with multimeter, repeat until desired resistance.Quote:
Originally Posted by iRoNeTiK
Well tonight I did the pencil mod for vmem and pencil mod for switching frequency. eVGA 7900gt CO, I got 670/990 so far with running atitool artifact free for 30 minutes and playing bf2 for an hour and benching with 3dmark05, so still some tests to do and time will tell but here is a link to my results collage, with 3dmark05, temps, cpu-z, powerstrip, and pics of the voltmods I did. I did the 1.5 voltmod and 2.23 vmem, the pic says 1.4 but that isnt true :)
CLICK ON IMAGE TO GET FULL SIZE
<a href="http://www.clanmkal.net/slutmonkey/seth1.png"><img src="http://www.clanmkal.net/slutmonkey/seth1.png" width="640" height="480" ALT="Results Collage"></img></a>
I'll run 3dmark03 and 06 later and let you know
My xfx 7900GTX has a differant layout. does anyone know how to volt mod the xfx 7900GTX? thanks
EDIT here is a pic of my card.
http://img199.imageshack.us/img199/7...0gtxpcb4uw.jpg
A good friend of mine who asked me to voltmod his XFX 7800GT has the same problem, the damn PCB layout is totally differnt than any of the guides here or also in the other forums so I have no idea how to do the mod. I guess the XFX's just set up their PCB's a little different?
Although I have been a member of this forum for almost a year now, this is my first post, never had to because I always understood your posts and most of the questions asked and been answered are also my questions. I read a lot of your threads here to just abosrb the knowledge imparted by the gutsy/extreme members for shouldering the risks of modding. I just want to express my gratitude to you guys,:worship: :worship: :worship:
Here is the mod I did plus the +.05 below that.
http://img218.imageshack.us/my.php?image=easy18zt.jpg
So the vgpu is at 1.55 and using Coolbits got 7900GT up to 725/1800, although the slider for memory tops out at 900, I suspect it can do better. I have chip on watercooling and temps are 45-48 under load. Although I built this system solely for gaming, I dont get to play with it all the time, maybe 4-5 hrs session at a time. Question is, will I be safe running the card at 1.55 with my gaming habit of just 4-5 hrs/day? Again thanks guys, you are awesome.:woot:
With temps like that and watercooling you're perfectly safe to run 1.55v IMO. I run 1.5v on my vf900cu and my temps aren't quite as good as yours and I've experienced no problems. I'd like to take this chance to thank you for not being one of the many who tend to post questions that have been answered time and again because they are too lazy to read. Belated welcome to xtremesystems.
BTW, nice OC on that opty.
what pasta is better for 7900gt in combi with vf900cu
Coollaboratory Liquid Pro or arctic silver V or any other suggestions.. ?
i want to try the 1.55v mod
Well, I dont know anybody who used a 7900 for over 2 months, let alone somebody with 1.55V runing through it, so you really cant say for sure. Although 1.55V is way above the norm for a 90nm chip (even 1.4V for the GTX is pushing it), as long as you provide sufficient cooling, especially for the voltage regulation circuitry, the risk should be quite low.Quote:
Originally Posted by TheSaint
Thanks, I like to read. This forum is like a Clancy or Ludlum book to me, or one of those books on the stores titled "Computers for Dummies" (like me) but, only on NITROUS:sonic:Quote:
Originally Posted by quijonsith
Thanks Deimos, I will try and run at that voltage I have for now and will keep an eye on this thread for early warning if anything happens to the guys who run at that voltage of above.
What is the max recomended Vmem voltage is it ok at 2.30-2.40v I am at 2.23v and i can't go past 890mhz 1780-DDR?
I wouldn't go much past where you already are gotheb1ues! 2.23v is pretty high over the stock voltage but I guess as long as your temps are decent and your not getting any artifacting you should be all set. I have seen and heard from people who have gone higher than you but not too many have! Another way to help come up with a max VMEM voltage is to keep an eye on the ratio of voltage increase to clockspeed increase. If you increase the voltage even more but your clockspeeds doesn't increase much at all than you'l know your getting close to maxing out both the clockspeed and voltage. There is no reason to keep increasing the voltage if the returns are negligable. What card do you have?
I agree. 2.23 is probably getting pretty close to the maximum (supposedly the 2.0v from the factory is actually an overvolt on these chips...but I have no idea if that is correct or not).
2.20 got me up to 920/1840, so I wouldn't say your "off" by much
You are correct 1.8v + or - .1v is what the spec sheet says for these memory ic's.:fact:Quote:
Originally Posted by Codeman05
I think some careful consideration is required. There are very good reasons why manufacturers choose such nominal voltage and maxium. The GPU and MEM chips are made on a very fine lithography process which doesnt allow such high volts, and typically over-volting leads to diminishing returns (if any). Perhaps you might need to look into other causes of instability or signal degredation. For instance, a lot of people who felt unsatisfied with 1.4V mod, got substantially better reults by increasing the swithcing frequency of the power regulation.Quote:
Originally Posted by Codeman05
I know this is xtremesystems, but all I'm saying is that using brute force to push voltage to the point of near failure is hardly constructive.