swapping CPU's - good ways to pull a CPU

[skeenna]

I wanted to put a full 040 cpu from a quadra 800 into an LC630.

has anyone done that? did it work?

what is the your favorite tool / method to use to pull the CPU?

TIA

 

[dualdflipflop]

I have a Quadra 605 which stock has a 68LC040... Yeah, sucks. Dana will tell you all about that. I recently changed out the processor with the full 68040 which, let me tell you, made such a difference.

I don't think I'm much help since I've never done that particular upgrade before, however I'll be here for moral support!

 

[TylerEss]

Yep, the 68040 and 68LC040 are pin-compatible and there's no good reason not to swap in a real 68040 to gain the FPU.

Edit: the 68LC040 might be better for extreme overclocking due to lower heat output and fewer internal parts that might not like to be overclocked.

 

[dualdflipflop]

I don't know, I found it to be a slight benefit having the FPU, and there was just enough room for mounting the heatsink that came off the 040 that I pulled from the Quadra 650 that I got it out of. Besides, the 650 was pretty much hosed except for the CPU... hardware wise. It was trashed when I found it (in other words... so what's a fella to do? eh.)

Hmm... Overclocking... nah, not for me.

 

[Flash!]

I've always found 040's to be very robust - I had a Q605 server up for about 3 months straight with a 25mHz 68040 overclocked to 33mHz, I pulled the fan (coz it was too noisy), no heat sink, another two Q605's in the same stack plus a monitor sitting on top (so minimal air flow).

When I did the overclock/upgrade and put it all together I didn't even really think about whether I was going to cook the processor or not. Then one day I thought hmmm maybe I should take a closer look so I opened her up and yes, it was very very warm.

No damage done though so that's a good thing. I guess it was so stable and did not crash because it was running as a http/ftp server, and I wasn't actually using it or doing anything intensive.

 

[ChristTrekker]

I wanted to put a full 040 cpu from a quadra 800 into an LC630.
has anyone done that? did it work?

what is the best tool to use to do the swap?

I pulled the 040 from a Q840 to use in my Mystic CC (LC 575 mobo). I think I used a small screwdriver to very gently work the corners up. You don't want to bend any pins, so work them in a round-robin fashion, a little more each time around until it is free enough to pull straight out. It works great.

 

[skeenna]

Thanks for all the replies, so far.

with regards to how to pull the CPU, does anyone have any more experiences to share on what tools you used and how you did it?

TIA

 

[Charlieman]

I modded a metal blanking plate from a PCI/ISA slot. The flange that is screwed onto the PC case is a bit thicker than the gap between a cpu socket and cpu. However it only takes a few minutes to reduce the thickness with a file. The greater area makes it easier to lift the chip than when using a screwdriver. Use it in the same way as described by ChristTrekker.

The same tool can be modded further for pulling PROMs etc. Reduce the width of the lange so that it will fit under the long ends of the PROM.

Daystar shipped a very nice cpu puller with the PowerCache boards that fit into the cpu socket on the IIcx, SE/30 and II.

 

[TylerEss]

I've always done the screwdriver trick. I like to get the widest, thinnest screwdriver I can find (less pressure = less chance of breakage). A sharp putty knife might work, or a straight razor blade if you're careful.

+1 get some device between the CPU and socket and gently work it up, moving around the chip to keep it level (prevent bending the pins).

+1 PCI slot blanker is prolly a good tool to use.

 

[beachycove]

If you are looking for a ready-to-hand tool, a 3/4" or 1" wood chisel (not razor sharp and used carefully) is what I have used a few times now. I use a gentle twisting action, which raises a side at a time just a smidgeon, and basically keep going round until the processor comes loose enough to pull by hand.

And, er, don't try to hammer it in!

 

[Quadrajet]

I actually have one of those chip puller tools, and like everything else, the tool made for the job works the best.

Otherwise, in a pinch I use a tiny screwdriver and slowly pry around the processor until it pops out.

Now on overclocking... I have had a Quadra 605 with a full '040/25 overclocked to 42Mhz running for five years 24/7, and it is extremely stable and everything works. It feels snappier than my 840av did.

I have a heatsink from an old power supply epoxied to the processor with no fan, and after running hard, the heatsink is only warm to the touch.

 

[bluekatt]

how does one overclock anyway ?

 

[Danamania]

I use a small paring knife - about 3" long. The important thing is to have something you can hold quite stable and wedge between the CPU and its socket, and lift just a little bit, while moving around the corners. It might take three or four rounds, but eventually it'll be loose enough to come out

bluekatt:

As for overclocking, it depends on the machine. Some of them have the frequency of the CPU controlled by an oscillator that you can swap out, others are controlled by a clock signal generator IC, which can be set for one of multiple speeds by moving surface mount resistors around on the logic board.

http://homepage.mac.com/schrier/mhz.html has much info on how to overclock various mac models.

Dana

 

[TylerEss]

Re: 25MHz 68040 running at 42MHz

Wow! The 40MHz Turbo040 in my SE/30 came with a 33MHz 68040 onboard, so it was factory overclocked. I couldn't get it to budge much past 40 even with a huge heatsink and fan fitted (it would run at 48 for about 10 minutes, but it would then crash).

I had to source a "real" 40MHz 68040 to get my SE/30 stable at 48MHz, and even with a nice heatsink/fan attached using the "arctic silver and super glue" method, 50MHz still isn't stable. It crashes about every 3 or 4 hours.

Good show on the 25MHz chip at 42MHz overclock.

 

[Quadraman]

I wanted to put a full 040 cpu from a quadra 800 into an LC630.
has anyone done that? did it work?

what is the your favorite tool / method to use to pull the CPU?

TIA

I recently put a full 040 into a Performa 631 to make it a Quadra 630. The chips have the same pinouts, just the FPU is disabled on the LC models. There is another mod you can do the 63x motherboards to raise the clock to 40mhz by swapping around some resistors. You'll need at least a 33mhz CPU to do it, though. A 25 likely won't clock that high. If you're really lucky, you may find a 40mhz chip on ebay. I found someone selling 2 of them last month and grabbed them both. You don't see the 40mhz ones that often anymore, so if you see one with BIN, grab it because it'll be gone if you think too long about it or try to snipe it near the end with a big bid. I would guess that since overclocking reduces the lifespan of chips, underclocking should have the opposite effect since the chip is running slower and cooler than at it's rated speed.

Favorite tool: butter knife [] ]'>

Be sure you pry up evenly all the way around the edges of the cpu so you don't bend or break any pins.

 

[madmax_2069]

i want to get my P475 running at 40mhz. i got the 40mhz cpu installed which is a full 040 but since the system is still stock its running at 25mhz.

i have seen sites that sell the crystal oscillator replacements to allow you to boot the system with no problems at that speed. and i have seen sites saying that replacing the PLL is the other way to obtain the 40mhz.

but i have read on a few of these sites that clock chipping will cause problems like only be able to select 640x480 screen resolution no matter if you have a monitor capable of displaying higher or having 1mb vram or both.

i want to obtain 40mhz with the system running like it was ment to run at 40mhz with full set of selectable screen resolutions

the only thing i need is the parts to do this mod like the 80mhz PLL and the crystal oscillator replacement and surface mount resistors of the proper type

 

[skeenna]

Finally got around to pulling the CPU out of the quadra 800 to swap with an LC 630.

I used a butter knife to pry the cpu out of both units.

Thanks to everyone for suggestions!

 

[Flash!]

Ladies and gentlemen, the butter knife is the winner! [] ]'>

 

[risc_management]

I actually have one of those chip puller tools, and like everything else, the tool made for the job works the best.
Otherwise, in a pinch I use a tiny screwdriver and slowly pry around the processor until it pops out.

Now on overclocking... I have had a Quadra 605 with a full '040/25 overclocked to 42Mhz running for five years 24/7, and it is extremely stable and everything works. It feels snappier than my 840av did.

I have a heatsink from an old power supply epoxied to the processor with no fan, and after running hard, the heatsink is only warm to the touch.

It may only be warm due to the epoxy being an excellent insulator.

Then again, the 040's run relatively cool compared to anything in fashion today.

When I first began swapping around 040's back in 1995, it was to move a full 040 25MHz from a Quadra 660av to a Performa 631CD. This test was for proof of concept, as there were no good online documents accessible to me as to what the true difference was other than FPU.

When I was ready to restore the LC back to the 631, I got in a hurry and bent the pins. Some of the pins may bend at the middle of the pin, rather than at the point where it meets the processor package. If this happens, it's hard to straighten them out.

In other words, my 660av still lives--The 631 does not.