oh .. so he maybe ended up with 0 ohms and fried the card ... the temperature drift of the VR is probably bigger than 50 ohms
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oh .. so he maybe ended up with 0 ohms and fried the card ... the temperature drift of the VR is probably bigger than 50 ohms
Yep, it fried when the VR drifted to 0... I'll bet money on it.
We're talking about 50 OHMS here, people... not 50K. :rolleyes:
How much voltage is at the mod point?
Could be that at the extremely low resistance levels the voltage is causing excessive amperage to overheat the VR.
still working good on yours right? get any records yet?:DQuote:
Originally Posted by Theta
Still good here, nothing major. I don't have water, so I'm not pushing past 1.35v. Up to you guys to go up to those heights.
The VR was never warm under testing, but now I'm using 1W fixed resistors - more insurance of no drift, as I'm sure you guys will agree. Too dangerous with a VR at these low ohms.
MMOuse said he'll show ya 4870 cf on ln2 and vmods later on tonight
Sounds like a plan! :DQuote:
Originally Posted by CCC
Why would it overheat the VR? Let say we have 3v in VR plots --> P = U²/R = 9/50 = 0.18w ...
Assuming that the tension deliverd to the chips can't be >3v and that the VR value can't be <50, you'll always be <0.18w.
On 8800GT, the Vgpu mod is done with a 500 ohm VR...
so this resistor seems to be ideal for the mod? 50 ohm 15 turn .75W (is .75w ok? could you go to .5w for a 25 turn Pot?)
yep looks great.:up:Quote:
Originally Posted by SNiiPE_DoGG
Put a fixed resistance and a VR in serie if you fear this :p:Quote:
Originally Posted by Theta
Pic pls, mine also is stock, cut from original one...Quote:
Originally Posted by adpr_02
How are you guys determining the voltage on the card for the 4870 the only pic I've seen in this thread is just a general area to try out unless I've missed something :confused: I'm going to solder a set of 4 10 ohm fixed resistors together and use that as the mod because I've had experience with vrs moving over time.
4870, VGPU and Pencil mod pic please :shrug:
Pictures 2 pages before: http://www.xtremesystems.org/forums/...&postcount=352
Below for the VR values.
Not sure if it has been 100% confirmed thoughQuote:
Originally Posted by jimmyz
To avoid the resistance getting too low I plan on using a 25-turn 100ohm trimpot connected to a fixed 8.2ohm resistor. Does it matter what wattage rating the fixed resistor has? I can get 0.25W, 0.6W 1W or 5W. The higher the better?
1W is high enough in every cases, don't worry for this. And I assume it is 1w with poor working conditions, which you won't have on your card
THETA
Can you post a real photo of your vmod?
Quote:
Originally Posted by CCC
Sexy I knew they could hit 1ghz I bet he could get some more on it too. Do you know his volts?
im thinking i will do this too because I can get nice metal oxide resistors at my local shop in 10 ohm, as i will be doing 24/7 at the volt mod and not LN2'ing or anything just a small voltage bump should be fine for meQuote:
Originally Posted by keninishna
Guys can you make a pencil mod for the 4870? I really don't like to void the warranty of the card.
pencil is not goodQuote:
Originally Posted by overcrash
for warranty: if you remove the mod and clean the vga you will havan't problem:D
@CCC : only one words " AMAZING " keep pushing it .....realy nice jobs Man..:up::up:
@CCC: Really good score,keep pushing... Can you try 05,06 vantage maybe?