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The HD 4870/50 Thread

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I did the vmod and I should have 1.36v under load I don't know how people are measuring the voltage but it seems to be working and temps seem to be ok no artifacts but if I go over 860 I get them. I'll probably go up to 1.41 volts tomarrow and see if I can hit 900+ on core. I modded the bios of the card but only to regulate the fan and Im using amdgpu tool to set the clocks.
 
Is a 500W Alim enough for two 4850 ?

Hello guys,

I already have one 4850, and I'd like to get another one in crossfire, but I'm wondering if my PSU will be able to handle everything inside my rig.
The PSU I have is a Antec's EarthWatts 500W. You can see in my signature the rig description (mainly Q6600 G0 and 4 HDDs)...

Thanks for the advices!
 
KENINISHNA

did the vmod and I should have 1.36v under load I don't know how people are measuring the voltage but it seems to be working and temps seem to be ok no artifacts but if I go over 860 I get them. I'll probably go up to 1.41 volts tomarrow and see if I can hit 900+ on core. I modded the bios of the card but only to regulate the fan and Im using amdgpu tool to set the clocks
.

hats off to you mate thats awsome...hmm i wouldnt mind trying to push up my oc but how safe is the modding? did u stress test it under those speeds?
 
Hello guys,

I already have one 4850, and I'd like to get another one in crossfire, but I'm wondering if my PSU will be able to handle everything inside my rig.
The PSU I have is a Antec's EarthWatts 500W. You can see in my signature the rig description (mainly Q6600 G0 and 4 HDDs)...

Thanks for the advices!

It may turn on and run, but I would not feel comfortable to suggest it for X-Fire. I'd recommend a minimum 600W unit (a good one at that). Post a thread in the power supply forum and we can take it from there. ;)

I did the vmod and I should have 1.36v under load I don't know how people are measuring the voltage but it seems to be working and temps seem to be ok no artifacts but if I go over 860 I get them. I'll probably go up to 1.41 volts tomarrow and see if I can hit 900+ on core. I modded the bios of the card but only to regulate the fan and Im using amdgpu tool to set the clocks.

ken, is it a pencil mod or a hard mod? How are you reading VCore? Does any software read it accurately?
KENINISHNA
hats off to you mate thats awsome...hmm i wouldnt mind trying to push up my oc but how safe is the modding? did u stress test it under those speeds?

You will have to bump you fan speed up > 50% if you push the clocks. Also, VMods are never really completely "safe" ;)
 
KENINISHNA

.

hats off to you mate thats awsome...hmm i wouldnt mind trying to push up my oc but how safe is the modding? did u stress test it under those speeds?

I only tested it for a few hours last night no real stress testing other than a couple vantage runs. the voltmod seems safe enough I hear though that the voltage regulators on the card can get hot and shut it down and putting some heatsinks on them helps. Temps on the core aren't bad though around 60c load with fan at 52%.

It may turn on and run, but I would not feel comfortable to suggest it for X-Fire. I'd recommend a minimum 600W unit (a good one at that). Post a thread in the power supply forum and we can take it from there. ;)



ken, is it a pencil mod or a hard mod? How are you reading VCore? Does any software read it accurately?


You will have to bump you fan speed up > 50% if you push the clocks. Also, VMods are never really completely "safe" ;)

Its a hard mod I just soldered 3 10 ohm resistors together. I don't know how to read vcore at the moment which is really dangerous but temps are ok so im not worried right now but as soon as I figure it out I'll tell you the actual voltage.
As for pencil mod the 4870 requires only about 20-30 ohms which is waay too low to pencil I feel much safer with just 2-3 resistors soldered onto the board. I guess its safe someone at XS allready killed a card but the guy used a 50k variable resistor and turned it all the way down to like 10 ohms which is just baad. As long as your soldering skills aren't terrible its not a hard mod to do.
 
I lowered the ohms to 20 and I was able to raise the clock an additional 10 mhz to 870 however I'm still not able to get an accurate voltage reading but heat is still pretty good. I'm thinking the 30 gauge kynar wire I used for the mod might be too small. I also played crysis on v high with x4 aa last night for about an hour and half with no problems some minor memory artifacts I might pencil mod my memory to make it more stable. The drivers though keep bugging out at first crysis would play for about 2 seconds then the drivers would crash so I upgraded to the 8.7 beta drivers and that worked until I rebooted now they crash crysis :shrug: 3dmark 06 when I upgraded the drivers got me around 11,000 points so I rebooted and now the drivers crash and I can't complete the bench but for some reason vantage runs fine at any given time. I'll try driver cleaner and reinstall the hotfix drivers later today to see if that fixes it other than that this card is sick I couldent play crysis at those settings with a gx2.
 
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I got a second card from a canadian site for 245.00 shipped:)

1 Visontek 4870and 1 Saphire 4870 in crossfire, both cards at 790/1100 stock volt and stock cooling.
 

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It may turn on and run, but I would not feel comfortable to suggest it for X-Fire. I'd recommend a minimum 600W unit (a good one at that). Post a thread in the power supply forum and we can take it from there. ;)

Well, after some research it ends out that my rig would pump something like 19.5A on the V12_1 line of the power supply, which is more than the 17A mentionned by the manufacturer. The 500W should be enough though...

I think I will pull back and keep only one card, this is the safest way, and it's enough to run any kind of games...
 
ahahha 30k + that is sum mad skillz rite there, what about higher rez?..makes me wanna buy a water cooling kit and clock my quad to 4gig cee what scores i can muster up :) good job!
 
hope you both noticed he's showing that score from 3D Mark 05.. but thats still a damn high score anyways, nice work HR :)
Nobody is gonna hit 30K in 06 using these cards without LN2 on everything including the power supply, monitor, keyboard and mouse. ;)
 
I'm thinking the 30 gauge kynar wire I used for the mod might be too small.

The wire size doesn't matter on a FB mod such as this, there's no real current flowing thru it ;)

I got a second card from a canadian site for 245.00 shipped:)

Nice! :D

Nobody is gonna hit 30K in 06 using these cards without LN2 on everything including the power supply, monitor, keyboard and mouse. ;)

What are you waiting for? :D
 
Just changed cooling on my hot card to a Duorb and -10°C. Was idling at 42°C and now at 32°C. :D
 
The wall of fame staff are pic mongers. ;)

Good start though. :D


@Supertrucker: what brand card are you using?

Having some trouble with 3DMark03 ATM...but will get a better pic up soon.

GPUZ.jpg
 
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