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Radeon HD 4850 Voltmods

u dont mention the volts u sere running it...also what mod?pencil or solder?
and u did it on a reference cooler????????u NEVER voltmod on stock!!!NEVER!!!!
 
There it is!PENCIL MOD!!!
It has happened to me too something similar.The card was unstable on cod4 and crashed after 3 minutes of play.I run it on 1,34volts and guess what?I measured the vcore and it was 1,24!!!The pencil is removed through time of palying due to air movement mostly and u have to reshade the resistor!After i did this it works great again at 1,34.So in your case there must have been sunned removement of pencil from the resistor and the card coldnt even boot.I t might have been posible to reshade and make it work again!!!Did u try that?
 
well u could try at least force a reflash through atiflash to the stock bios and see what happens.I am curious for your case cos from the 4 months i vae it i only bought musashi 4 days ago,and all this time i had it on 1,34/2.45 core mem@781/1150 with no probs!!
 
yeah it will be great!!!!!but does your mobo support it?!!!And now that i think of it,why dont u RMA the card???????Put the stock cooler back on and send it back..??
 
pyckmeister banned for posting rickrolled link
 
Excellence said:
i SCRIBBLED it, both of the mods and nothing works it has no affect, how could i convince ncix its broken even thought it works fine but wont pencil mod?
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theorw said:
From what u say it sounds like u want to rma your card right?
Well theres one way i use and it has always worked!Flash your card with a bios(even the original) and at the moment it says:dont turn off or restart ,DO IT!!!RESTART your pc and the card wont have a bios to boot and it will be in operational!!!
Of course the shop wont susspect that!Or will it??
Click to expand...

That is the best way, and it is reversible with another bios flash.

But you should know that when you die you will go to tech-hell for doing this... If you posted this on XS (if it was up) you would get a ban.
 
Drizzt5 said:
That is the best way, and it is reversible with another bios flash.

But you should know that when you die you will go to tech-hell for doing this... If you posted this on XS (if it was up) you would get a ban.
Click to expand...

REALLY???I didnt know that...But its well known way for RMA!!!Anyway from now on i ll just refer to it as the UNFORTUNATE BLACK OUT DURING FLASHING.Is that LEGAL???!!!!:laugh::laugh::laugh:
 
burn my las gpu on this. XD
 
I am having a hard time figuring out what resistor I need for a permanent volt mod. How many watts does it need to be?

Can some please direct me in the right way for the resistor I need. Thanks!
 
xfx 4850/4830 non-reference pcb

shot of the back
xfx-4850-scan-back.jpg


front
xfx-4850-scan-front.jpg
 
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This is the XFX card right?
With NON REFERENCE design it will be difficult to find the mod man...
 
Has anyone else found that when they measure their voltages before doing any mods that it is higher than it should be? I tweaked my voltage up to 1.158v by modifying a CCC profile but when I took the multimeter to my card it is showing 1.198v.
 
TrekBMX18 said:
Has anyone else found that when they measure their voltages before doing any mods that it is higher than it should be? I tweaked my voltage up to 1.158v by modifying a CCC profile but when I took the multimeter to my card it is showing 1.198v.
Click to expand...

Your multimeter could be bad.
 
TrekBMX18 said:
No, my multimeter is definately working fine. Tried multiple different ones.
Click to expand...

Have your temps gone up a lot? Idk never heard of that happening.
 
results

voltmodded my Sapphire Radeon 4850 Toxic a few weeks ago (its reference design with high quality ram, that can do 1200 memclock for sure)...despite it had an vf-900 on it, its load temperatures went to 100ish temperatures:twitch: i improved it to 90ish temperatures mit liquid metal (which one time during a hot period here and many hours intensive gaming at those temperatures somehow lost 90% of its volume and truh touch of the badly constructed fan mounting it formed an air pocket somehow. neithertheless i got 780-790 corestable and somewhat 1225-1250 ddr3 clock (theire samsung 1200mhz rated,lightly voltmodded). later my psu degraded, i somehow erased mod because i thought it somehow degraded truh the fans pushing air at it, it crashed me constantly (but in fact it was my psu which was degraded,not able to hold the clocks and crashing thru overload, and its dieing right here in this rig atm, i sometimes hear a quiet humming frum it, while i write this). with new mods i tried i wasnt able to do more than 765-735 in 2 weeks trying . i got me a miltimeter and found that nothing beyound 1,25 could be given on the card before it died heatcrash at 765 (way lower than former mod, despite i had no multimeter in the beginning)... so 1,25 was not that what was needed to get to 800 stable... memory clocking good though producing more heat and energy fluctuations... with only VERY MILD increases i was able to reach the 1250 realm with 2,3v vmem again. the temps went like 5c° up just trough 25mhz clock increase. on the attempt to reseat the cooler with new paste (in fact it was tacens silver goop, with just 25% silver, had nothing else). on the applycation in a not so well lit room, i somehow got a tiny amount of the goop on the transistors surrounding the die, but i didnt noticed and remounted the VF-900. after sticking it in my rig, i booted,went to bios,bios crashed with screen error
i rebootet and tryied the foolish attempt to boot in windows. it hummed and crackled, screen went black, card crapped.... (in fact im too poor to just go buy a new one like i prefer, i cleaned card and rmad, hope i have luck, or i will have to stay onboard for a while, but thats nasty, i cant play crysis properly, i have to vomit if the config is lower than 1152x864 (without aa and af) and at least high (even that seems too low). am i sent to techhell now?:)
 
Velvet Wafer said:
voltmodded my Sapphire Radeon 4850 Toxic a few weeks ago (its reference design with high quality ram, that can do 1200 memclock for sure)...despite it had an vf-900 on it, its load temperatures went to 100ish temperatures:twitch: i improved it to 90ish temperatures mit liquid metal (which one time during a hot period here and many hours intensive gaming at those temperatures somehow lost 90% of its volume and truh touch of the badly constructed fan mounting it formed an air pocket somehow. neithertheless i got 780-790 corestable and somewhat 1225-1250 ddr3 clock (theire samsung 1200mhz rated,lightly voltmodded). later my psu degraded, i somehow erased mod because i thought it somehow degraded truh the fans pushing air at it, it crashed me constantly (but in fact it was my psu which was degraded,not able to hold the clocks and crashing thru overload, and its dieing right here in this rig atm, i sometimes hear a quiet humming frum it, while i write this). with new mods i tried i wasnt able to do more than 765-735 in 2 weeks trying . i got me a miltimeter and found that nothing beyound 1,25 could be given on the card before it died heatcrash at 765 (way lower than former mod, despite i had no multimeter in the beginning)... so 1,25 was not that what was needed to get to 800 stable... memory clocking good though producing more heat and energy fluctuations... with only VERY MILD increases i was able to reach the 1250 realm with 2,3v vmem again. the temps went like 5c° up just trough 25mhz clock increase. on the attempt to reseat the cooler with new paste (in fact it was tacens silver goop, with just 25% silver, had nothing else). on the applycation in a not so well lit room, i somehow got a tiny amount of the goop on the transistors surrounding the die, but i didnt noticed and remounted the VF-900. after sticking it in my rig, i booted,went to bios,bios crashed with screen error
i rebootet and tryied the foolish attempt to boot in windows. it hummed and crackled, screen went black, card crapped.... (in fact im too poor to just go buy a new one like i prefer, i cleaned card and rmad, hope i have luck, or i will have to stay onboard for a while, but thats nasty, i cant play crysis properly, i have to vomit if the config is lower than 1152x864 (without aa and af) and at least high (even that seems too low). am i sent to techhell now?:)
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If I were you, I would take off the vmem mod. I have found out the hard way that raising the voltage on most video cards' mem chips is a bad idea, unless they are undervolted from the factory.

As far as the core, the VF-900 isn't the best cooler to use for these cards. It was designed in a time that the heat output of our cards was lower in general. If you want to vmod, upgrade your cooler to something a bit stronger.

Also, if your psu is dieing, quit using the computer. It can kill absolutely everything hooked up to it if/when it blows. Mobo, cpu, ram, HDD's and all.
 
I know its dangerous, but i use it with undervolting to 1.163v for my proc,and 2v to my rams. as soon as i hear thunder,the pc will be shut down by me, other guy asked me to do so if that happens. do you know how much dangerous the vmem-mod is on samsung chips? theyre rated for 1200 0.8ns (theyre K4J52324QH-BJ08)... and 2.05V (on the next card, i want to do everything right...and i know that this baby needs bandwith more than coreclock.)

im having a twin turbo sent to me with my new psu, dont worry^^
 
Velvet Wafer said:
I know its dangerous, but i use it with undervolting to 1.163v for my proc,and 2v to my rams. as soon as i hear thunder,the pc will be shut down by me, other guy asked me to do so if that happens. do you know how much dangerous the vmem-mod is on samsung chips? theyre rated for 1200 0.8ns (theyre K4J52324QH-BJ08)... and 2.05V (on the next card, i want to do everything right...and i know that this baby needs bandwith more than coreclock.)

im having a twin turbo sent to me with my new psu, dont worry^^
Click to expand...

I just don't do vmem mods anymore, unless the card comes with the ram voltage lower than it's rated to handle. So if the mem is rated for 2.0V, but the card comes at 1.8v, I'll mod up to the 2.0V. Every single time I've ever gone over the factory rating, my memory has degraded over time, and eventually died.
 
its rated at 2,05 and ran 2,0-2,1... dangerous?
 
Velvet Wafer said:
its rated at 2,05 and ran 2,0-2,1... dangerous?
Click to expand...

That might be OK, but I wouldn't go any higher at all. The Samsungs on my 8800GT were rated for 2.0, I ran them at 2.06 and they died on me. So do it at your own risk.
 
luckily, everything beyond 2.2 produced too much heat to go further... thru this i was able to push to 1250 stable. i had stock-heatsink-temps, but i needed bigger 92mm fan on the vf900, second 92 mm fan for the pwms, 3 fans pushing fresh air, one blowing it out of the case. if the accelero isnt cool enough, i will repeat the process with 120mm fans on the card this time.(i will first use arctic ceramique, but later maybe will use liquid metal) what dou you guess the toxic can do with adequate cooling? on core and memory?.. 1200 mem are stable without voltage increase
 
W1zzard , I saw you're the ''MAN'' here , I have a question : After making the voltmod I have to increase Core vaules with RBE tools and flash it with atiflash , etc ? ... Beacause I' ve been doing bios flashing and the Overdrive option in CCC disappeared after flashing...
By the way , I haven't done any vmod yet.. only changed values in RBE tool .
Thank you ;)
 
for voltage change, try ati tray tools... that helped for me, after doing the mod
 
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