How do you lap a GF4 Ti4200?

How do you lap a GF4 Ti4200?

What grit of the sand paper should I get? 600? 1000?

Is there a guide/url with step to step on how to lap a GPU

Let me go ahead and say don't lap it. It might help but then again it might trash your card. I had a Geforce II GTS that I decided I wanted to overclock. The GPU wasn't flat naturally so I figured I'd try to lap it. No matter how much I did, I couldn't get rid of the indention in the center and the temperatures never seemed to change. Took it out for one more lapping session and when I put it back in I had killed it. Not sure exactly what I did but I trashed the card. I'd just stick to lapping the heatsink you are going to put on it or the stock one and be happy with it. Chances are, you won't get that much of an improvement out of lapping the GPU in relation to the risk of tearing up a good card.

start with a lower grit.. and keep on going higher until you get bored.

/me is waiting for someone to pull the "very carefully" joke.

-Toysrme

I would be afraid to so much as touch the GPU for fear of killing it.

Lap the heatsink with 600wet going up to 2000wet, then grease it with AS3 and let it lie at that.

"VERY CAREFULLY" use a Electric Belt Sander starting at lik 200grit

Well, always cover your card and most of the area surrounding the core with tape. That way no dust, grit, or flakes get in the pcb areas. Then you start with 600 grit wet/dry, but keep it DRY, of course. Use your heatsink or an extra heatsink as the flat surface to support the sandpaper. simply wrap the sandpaper around the heatsink and use the flat side as your sanding surface. Every time you get a dust-packed area of sandpaper, move to a new area. It will sand quicker that way. Keep dust on the protective tape to a minimum by blowing it away. after you sand all text off of the shiny center (which means everything else matches it on the surface), you can now go to 1000 to 2000 grit for a final polish. 1000 grit is fine, really. After that, you clean all surfaces with a paper towel and ethyl/isopropyl alcohol. Acetone or ethyl acetate is OK for CPUs, but not circuit boards, so leave the finger nail polish remover in the bathroom. After that, apply a small amount of artic silver, smooth it out like on a cpu, and apply the heatsink. There you go!

Let me add, continually ground yourself to your case while you do this. Just touch a bare metal spot avery few minutes or so to be safe. Leave your case plugged in, just turn off the back switch and the circuit cannot close, but the ground is intact.

typhoonmike said:

Let me go ahead and say don't lap it. It might help but then again it might trash your card. I had a Geforce II GTS that I decided I wanted to overclock. The GPU wasn't flat naturally so I figured I'd try to lap it. No matter how much I did, I couldn't get rid of the indention in the center and the temperatures never seemed to change. Took it out for one more lapping session and when I put it back in I had killed it. Not sure exactly what I did but I trashed the card. I'd just stick to lapping the heatsink you are going to put on it or the stock one and be happy with it. Chances are, you won't get that much of an improvement out of lapping the GPU in relation to the risk of tearing up a good card.

Click to expand...

On Geforce 2s (and 3s) the core is like this:

\___/ so lapping is very useful. You just lapped too much, went past the copper, and into the core.

Are radeon 8500le cores concave also?

I'm gonna try this on an older card first... and if I dont kill it, Then my radeon. Then a bigger heatsink/fan and bga ramsinks.

AntmanMike said:

On Geforce 2s (and 3s) the core is like this:

\___/ so lapping is very useful. You just lapped too much, went past the copper, and into the core.

Click to expand...

Well actually I never got to the copper. That was my problem. I'd seen images of where other people had lapped until you got to the copper and they said they were done. I figured I was safe to get to the copper. It never showed up. Not even a hint of copper. Just decided I'd lapped enough and put it into the system and it was dead.

Thanks guys!!!

I lapped my GF4's GPU and HSF...... HSF shows the alluminium and its shiny and smoth..... However, I did not lapy my GPU to the copper layer it's alluminium surface as well and I have lap it for 30 min.

first with a 80 GRIT (wet) then 320grit (dry) then 600grit (dry) and finally 600grit (wet) The card works great now and I am happy camper. Now I just need to find 4 RAM SINK for the card and some epoxy ...

Well glad it worked. If you are looking for something to stick the ram sinks on with you could try the Arctic Silver epoxy stuff. Not sure where I bought mine since it's been over a year but it does hold well.

bump

Well since we're on the topic of ramsinks, does anybody know of a comparison online between thermal epoxy and frag tape? Does it matter that much?