Will I need to lap an Alpha P7125 to get better performance? NEW PROBLEM: It won't attach right!!

[Swanny]

I just bought an Alpha P7125 for my Slot A Athlon 800 that is running at 850 with the stock fan. I'm hoping the new HSF will be here on Friday, but it might be Monday Anyway, I was wondering if I will need to lap the base in order to get the best contact and performance. I was thinking maybe not because it contacts with the heatplate which probably isn't flat anyway, but I could be wrong.

Thanks,
Swan

 

[cnhoff]

I don't know that sink, but my PAL6035 has a mirror like finish, so any lapping would be counterproductive in that case.

 

[Noriaki]

The P7125's copper inlay was very smooth when I had one.

I woudln't have lapped it...

 

[Swanny]

All right, thanks guys. My first thought was to not lap it anyway, but I ordered a Blorb at the same time and I'm going to lap that. So I thought while I was at it.... But I guess I'll just stick to lapping the Blorb. I don't want to harm it or anything.

 

[SDOG34]

mine 6035 was nice and shiny too, but it had some major machine grooves in it. it just depends on how the surface looks to you. it can be more shiny than a mirror, but if it has any grooves in it than lapping is a bonus. do whatever youre comfortable with

 

[WarCon]

And while my PAL 6035 looked really shiny it was slightly convex, I couldn't actually tell until I started lapping it. It wasn't as bad as every other heatsink in my system though. They were really bad. Video Card and Northbridge both sucked, but you wanna hear the kicker is my northbridge center has a little circular indent in it. I am a freak though, so I took an old copper penny and lapped it really flat and really skinny and put it in between (with Arctic Silver) so I didn't have to fill it with Arctic Silver. Still not sure though which would of been better though. Nothing seems to help this lame board get over 139fsb and be stable.

 

[Swanny]

WarCon: If it was an all copper penny then it might help. If it is a zinc filled one with the copper coating it probably isn't helping much I can't remember the date they switched to zinc filled, but I think it was in the 70's.

 

[Swanny]

I just got to thinking. Would it help to lap the heat plate itself? I'm sure it can't be very smooth. I think there are some scratches in it from getting that old thermal pad off it Does anyone have some suggestions on that?

 

[WarCon]

I made sure it was old, I got a 1950's penny to make sure (was still an alloy, but was mostly copper). And yeah it wouldn't hurt to lap the heatplate too.

 

[Swanny]

OK, I guess I'll just have a regular lapping party then
WarCon: Wasn't it you that had something in your signature about a rolling blackout a while ago? I liked that You should put it back in there

 

[Technonut]

There was an article some time ago about lapping the heatplate on some site. (Can't remember which one) Anyway, it was found that it indeed could use some lapping. If in doubt, whip out a good straight edge.

 

[Swanny]

Technonut: That was my thought. I also thought it might be good to get that paint off there. It probably doesn't do much to help heat transfer.

And there was one other thing I thought of. I have some arctic silver II, but I don't want to waste it all and put it all over the heatsink. Should I just put it over the core area and use some regular paste for the rest of it? Or should I leave the rest just metal to metal?

Thanks,
Swan

 

[Technonut]

Out of the many that I have done, I only applied thermal compound to the core area of the heatsink.

EDIT: If you look closely at an installed P7125, you will see that the heatsink only makes complete contact around the core area of the heatplate, not around the cache chip areas.

 

[Swanny]

OK, I've got a new problem. The heatsink won't attach quite right to the heatplate. Someone tell me what I'm doing wrong please!

I know I'm using the right screws, they're the only ones that fit. The screws go into the heatplate and I tighten them. But I can pull on it and the heatsink comes partially off, so I know it isn't getting good contact. But then I push it back on and the screws seem to be back in place. They won't tighten anymore with the screwdriver. I can't think what is happening.

Swan

 

[Technonut]

The screws are self tapping. You should put a dab of thermal grease on the screw threads so any metal filings will stick to the grease, and not fall through. You must put a good bit of pressure down on the screws when turning them since they are self tapping. If you picked up a used one, there may be a chance that the threads are shot, and you may need to try to find self tapping screws the same length, but a little larger diameter.

 

[Swanny]

What exactly does self tapping mean? I don't want to overscrew them for fear of stripping the screws. And it was brand new, so they should be fine. So I just need take them out and then put more pressume on them while screwing? Pardon my ignorance

 

[Technonut]

Self tapping just means that the srcews cut their own thread into the holes in the heatplate. Every one that I have done, I had to press down pretty hard while screwing them in until they caught and tightened up.

 

[Swanny]

Ok, I'll try that. Thanks

 

[Swanny]

It seems to be working right now. On to the GFD adjustments!