ATI 4850/4870 voltmod thread

[r4st4m4n]

@dejanh - What are you using to measure the VRM temps ?

Personnally I bought a chipset heatsink a bit like this one:


Cut it in half, slapped it on the vitek and pulse chips and bent slightly the fins to make way to the HR03-GT. But I don't have any IR thermometers to check if the temperature improved. Everest 4.50 tells me it doesn't but everest readins seems to be wrong ...

[dejanh]

I too am using Everest, but to me the temps seem right. When the VRMs are showing as > 100 they are pretty damn hot, you cannot even touch the board. With FurMark, they get up to 126C

Either way, see the attachment for yourself

By the way, VITEC and Pulse chips are not the ones heating up like mad, it is five little chips next to the VITEC and Pulse when looking towards the back of the card. It is the ones that the stock cooler would touch with that foam stuff just at the edge of the fan opening.

Edit: it is the god damn VRMs. Or something on the back of the board. I just moved my 120mm fan to blow directly onto the back of the card and guess what, as I am typing this I am 322 seconds into FurMark and still going no problem. By the time I finish this it will be over 7 minutes of FurMark at 850/1150, I never managed to do that so far. Screen shot is included (still running too...)

[dejanh]

Well, it seems that the VRMs are in fact the reason for limited performance. They are not being cooled adequately to deal with the excess volts when volt modding. If I place a 120mm blowing directly onto the VRMs I can push the volts to 1.45 and the core to 880-890 with rock solid stability. At the same time, I can push the memory higher as well to 1175 or even 1200. But this is all and only with much more cooling on the VRMs. I think that with a massive VRM heatsink and a fan I could likely break 900 on air. Bah, what the heck do I do now to cool the VRMs? Maybe I should try that Thermalright MOSFET heatsink I pointed out earlier...

[LuxZg]

That's a good idea, but it unfortunately does not work for the 4870.

(1) The stock cooler does not have a specific VRM heatsink. It is just touching the VRMs with the frame of the whole stock cooler. Not much cooling going on there either as the stock stuff burns under the heat of the VRMs.
(2) It seems a heatsink alone is not enough on the 4870 VRMs. They just get too hot.

@1) In fact 4870 has even better solution, do it this way:

Just DO NOT PUT THOSE FEW MEMORY HEATSINKS IN THAT HOLE LIKE ON THIS PICTURE! Just use the red plate, and nothing else. If you want, you can stick few more heatsinks on top of red plate to have more dissipation space, but I haven't tested it so don't know if it would help.

@2) ofcourse heatsink is not enough, you have tu have AIR running over it So just add your HR-03 once you put this red plate, and than stick a 120mm fan on top of it si it pushes some air over the rear of the red plate if possible - like this

Since HR-03 is smaller than S1 (on picture), and is mostly over GPU socket, the fan probably won't be pushing a lot of air over VRM part in the rear, so you can maybe add one more 120mm fan just over where VRMs are like you've said you did in the later posts.

And that's it!

[8800's@over]

- People, you know the most about the voltage is possible only by increasing the voltage to obtain the BIOS?

[drizzt5]

Sinks originais voltam para os Mosfets


]

Are you using part of the orignal cooling that came with the 4850?

the soon to be released Accelero Twin Turbo might do a good job of cooling the VRM's. its dual fan design looks like it will force cool air over the entire video card. they were supposed to be released last month and no sign of them yet. maybe the delay in release has something to do with the hot VRM's on our 4870's. hopefully the people at AC are working on a good cooling solution. they specifically mention the 4870 on its list of supported cards.

Is that just a regular S1 with a fancy fan system on it? -__-

This is what my 4850 will look like :P This is what my 8800 gt currently has


Oh, and my 4850 is at my front door. YES!

[LuxZg]

Is that just a regular S1 with a fancy fan system on it? -__-

IMHO, AC Twin Turbo is inferior to S1. It's not exactly same heatsink, and fans are also not exactly the same as Turbo Module. HS is smaller, an that's why I'm saying it's inferior, but we'll have to wait and see the results. On the other hand, I preffer 2x120mm rather than 2x80mm

[stingush]

here's a very high quality picture of my card and my sittuasion... the card doesn't work at the moment, is there anything i can do? :

[mth91]

One thing i've learned in my year and a half of overclocking is that w1zzard is right. Those #2 and #3 temps are not vrm's and memory. I have good heatsinks on my vrm's and memory, and a 130cfm fan blowing over them, and the temperatures did not improve when I put that fan on there, which proves that they are part of the chip itself.

To the guy above me, no, with damage like that there's nothing that you can do about it. Sorry.

[SNiiPE_DoGG]

here's a very high quality picture of my card and my sittuasion... the card doesn't work at the moment, is there anything i can do? :

clean off all that flux and maybe we can get a better look at the pcb to see if its actually damaged. use an eyeglass screwdriver very carefully and lightly to scrape at the flux (all the brow "stuff") and it should flake off pretty easily

[deathman20]

here's a very high quality picture of my card and my sittuasion... the card doesn't work at the moment, is there anything i can do? :

Sorry to say but thats a dead card. If you could even replace the parts on top, no telling how much internal damage is done on the PCB. What happened?

[babalouj]

clean off all that flux and maybe we can get a better look at the pcb to see if its actually damaged. use an eyeglass screwdriver very carefully and lightly to scrape at the flux (all the brow "stuff") and it should flake off pretty easily

Just use rubbing alcohol or acetone, the flux will come right off.

[deathman20]

latest everest beta can show vrm temps, so can the next gpu-z version. gpu temp #1/#2/#3 in gpu-z are not the VRM temps

Can the next one read it on the 4850's though? Is there a VRM sensor for the card even? I know it doesn't show up in Everest for mine but not sure if thats because I got 2 cards or not.

[stingush]

i also think its dead... but i think that after i will clean the flux i will get it back to the store and they will replace it... i think its almost unnoticeable...

[W1zzard]

Can the next one read it on the 4850's though? Is there a VRM sensor for the card even? I know it doesn't show up in Everest for mine but not sure if thats because I got 2 cards or not.

no, 4850 does not have the voltage regulator ic that the 4870 has, so no vrm temp readings. see the thread here about "gpu temp #2 is vrm?"

[Tech Niques]

here's a very high quality picture of my card and my sittuasion... the card doesn't work at the moment, is there anything i can do? :

It looks like you have board damage there. Try to clean the flux off but I highly doubt that it'll work.

You can return the card to the store. I returned mine back back to Best Buy and got a new one but I'm not proud of doing so.

The new one is clocked to 850/1100 though.

[dejanh]

@1) In fact 4870 has even better solution, do it this way:

Just DO NOT PUT THOSE FEW MEMORY HEATSINKS IN THAT HOLE LIKE ON THIS PICTURE! Just use the red plate, and nothing else. If you want, you can stick few more heatsinks on top of red plate to have more dissipation space, but I haven't tested it so don't know if it would help.

@2) ofcourse heatsink is not enough, you have tu have AIR running over it So just add your HR-03 once you put this red plate, and than stick a 120mm fan on top of it si it pushes some air over the rear of the red plate if possible - like this

Since HR-03 is smaller than S1 (on picture), and is mostly over GPU socket, the fan probably won't be pushing a lot of air over VRM part in the rear, so you can maybe add one more 120mm fan just over where VRMs are like you've said you did in the later posts.

And that's it!

That's a good idea. However, the stock plate cannot touch the VRMs or the memory chips. I need to use thermal pads in between and they suck bollocks. Is there any way to get the stock plate lower to the card to a point where you do not have to use pads but can use AS5?

[xMrBunglex]

IMHO, AC Twin Turbo is inferior to S1. It's not exactly same heatsink, and fans are also not exactly the same as Turbo Module. HS is smaller, an that's why I'm saying it's inferior, but we'll have to wait and see the results. On the other hand, I preffer 2x120mm rather than 2x80mm

the nice thing about the Twin Turbo is that it will fit in two slots, so it's CrossFire compatible. my motherboard only has one empty slot between my PCI-E slots, so i can't use giant heatsinks.

i also like the fact that it has two fans - one directly over the GPU and memory and the other fan over the VRM's. it looks like a solid design to me. i'll probably buy a pair when they're released and report my results.

[Barr3l Rid3r]

Are you using part of the orignal cooling that came with the 4850?

Is that just a regular S1 with a fancy fan system on it? -__-

This is what my 4850 will look like :P This is what my 8800 gt currently has


Oh, and my 4850 is at my front door. YES!

No thats a Zalman VF1000, and yes I'm using part of the original cooling.

[stingush]

ok went to the store today and they have replaced me the card by a new one looks like this at the moment...(just waiting for a voltmod but i'm not sure im gonna make one after what happend) :

[LuxZg]

stingush - LOL @ Intel fans on Accelero But those are very good fans usualy, so nice idea I still preffer 120mm though

[stingush]

im 2 lazy to go to the store and buy 2 120mm fans... also i dont think there's so much diffrence between the intel and 2 120mm fans cause those are VERY powerful and efficient... it can do like 70-80CFM each...
and the temps are 36 idle and 47 load when ambient is like 27-30...(outside here its like 34-36)

[dejanh]

No more 4870 XOC. I got rid of it. That card has been more headache than it's worth. All of the XOCs in fact are junk. There has been no people reporting it to work properly so far, and even NCIX staff admitted that they are getting unusually large number of returns on the 4870 XOC cards, and for that matter on the 4870s in general. At least the BIOS is released, as useless as it is really. Looks like I'm back to using my lowly 9600GT for a while still, until all the kinks are removed from RV770 or NVIDIA potentially trounces them with the new 55nm GPU. At least I can run the 9600GT at 870/2147/1100 (2200 effective)

Now that's an OC from stock 675/1665/975

[dejanh]

I want to see some watercooling block made for these cards. All these huge heatsinks and fans you guys are using is funny stuff indeed lol.

As for Core voltmods, i noticed while changing my fan speeds that there is a corevoltage section also im guessing 3d volts are 1.12 volts. Cant you just change the voltage to whatever you want through there instead of soldering or bios flashing your card. ? Also how are you guys getting passed the 700 limit in the CCC i dont feal like digging this up through the 100 threads on these forums so can someone here tell me plz. Im using the stock cooler and all my games run fine so i dont care much about ocing past 700/1100 i noticed my fps only goes up like 6 so its not worth it IMO specially with this noisy stock fan and temps reaching 70c at 45% fan speed any higher and the fan becomes obnoxcious.

Cant wait for a waterblock...

Agreed, some better cooling is needed, lol. I would love a CoolIT system only for cards, so I don't have to have water on everything.

Now, you'd think you can change your core volts there wouldn't you? Well, they are display-only values so enjoy looking at them Seriously though, you can't set voltages there.

[LuxZg]

I want to see some watercooling block made for these cards. All these huge heatsinks and fans you guys are using is funny stuff indeed lol. <cut> Cant wait for a waterblock...

Well, watercooling is even more funny than these large air-coolers
You have one "heatsink" that's REALLY large (radiator), and 2-3 big fans on it (if you want it to cool whole system), so you're already at the same weight/size/fans amount us with common air coolers are, plus you have to bother with liquids and pumps

Now, if you would have fridge-cooling, that would be altogether different stuff