68kMLA Classic Interface
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| Upgrading to Full 68040 - Heatsink Needed? | |
| Posted by: Guybrush3pwood on 2016-04-18 13:53:07 I actually found a couple at work. They're slightly smaller, but I think they'll be ok? My plan is to use a little super glue in each corner and some Arctic silver in the center. That should be ok, right?  | |
| Posted by: Macdrone on 2016-04-18 14:26:50 thats what I use and no issues so far. There is some double sided thermal tape or thermal compound but the paste and super glue spots with no issues so far. | |
| Posted by: Guybrush3pwood on 2016-04-18 16:19:20 How do I set the clock speed on the new processor? Never done it on these old macs before. | |
| Posted by: Macdrone on 2016-04-18 16:26:43 http://lowendmac.com/2014/overclocking-the-mac-quadra-series/ check here they have links to the ones that can be changed and how. | |
| Posted by: Byrd on 2016-04-18 16:27:16 Either by adjusting the multiplier of the CPU by adjusting some (small) resistors on the motherboard, or adjusting the frequency of the CPU by replacing the clock crystal - all models differ. I've used GPU, 486, northbridge heatsinks on my '040 CPUs to great effect - doesn't need much (if anything), but the cooler the better in these old dears. | |
| Posted by: Guybrush3pwood on 2016-04-18 16:31:29 Holy crap, didn't realize this was that complicated. Thought I could just plug and play. Ah well, screw it. Bought the wrong processor anyway. This is all more trouble than it's worth. | |
| Posted by: Byrd on 2016-04-18 16:42:15 Yes, it is plug and play to switch an LC040 to full 040 - it's only if you want to overclock the CPU you need to perform the resistor and/or crystal swap. And wrong CPU, as in speed? A 25Mhz 040 will probably drop in and run fine at 33Mhz, and a 33Mhz will down clock to 25Mhz without any adjustments. | |
| Posted by: Unknown_K on 2016-04-18 16:47:36 On a 68K mac you more then likely just need to change the crystal oscillator assuming the motherboard can run at the speed you selected. AN LC to full 040 swap needs no changes as long as the speeds are the same. | |
| Posted by: Guybrush3pwood on 2016-04-18 16:50:33 Ok, not sure what anyone is saying. The plan was to swap the stock cpu on my LC 575 with this: http://m.ebay.com/itm/111633589714?euid=53fb61ae6fb34856a8be059ee404075d&_mwBanner=1 But I'm assuming that since my stock runs at 33mhz, and the one I bought runs at 33mhz, there's probably little point in doing so, correct? | |
| Posted by: rsolberg on 2016-04-18 17:01:37 I bought one from the same seller and did the upgrade on the same logic board as you did. Applications that take advantage of the full 68040's floating point unit will be dramatically faster than with the original 68LC040 processor. On the LC version, floating point operations are emulated in software, which can take 10-20x as long. Non floating point operations will run about the same. Some software requires a floating point unit and will not run on your original 68LC040. As for frequency, hardware on the logic board, not the processor determines the speed. If you found a 40MHz 68040, it would run at 33MHz unless you modify your logic board (as per the links others have posted.) In short, you bought the right processor for your machine. Some applications will be hugely faster, others will be the same. Given the mask codes the seller has, a heatsink is not mandatory, but is a good idea. | |
| Posted by: Guybrush3pwood on 2016-04-18 17:02:52 Ok, so it's still a good idea to do the swap then? | |
| Posted by: Floofies on 2016-04-18 17:03:56 The speed of the processor is determined by the logic board... there is no such thing as a "33/40MHz 68040". Although, 68040's can have different masks (the coolest being "L88M") which make them run cooler, and more stable. | |
| Posted by: Macdrone on 2016-04-18 17:08:45 putting a full 040 will give you gain, its a co processor . The issue is if you want to overclock to squeeze out some extra mhz. | |
Posted by: rsolberg on 2016-04-18 17:09:57Ok, so it's still a good idea to do the swap then?Yup. I did the same swap and I'm happy with the result. | |
| Posted by: techknight on 2016-04-18 18:44:15 I am sitting here just trying to figure out what software we could use today, that would take advantage of the co-processor? | |
| Posted by: Unknown_K on 2016-04-18 19:18:49 Microsoft Excel will for one, major reason I purchased a Cyrix 387 40mhz back in the early 90's for my 386DX/40 machine. Any compression software (Stuffit), jpeg converting software of the era, Photoshop. | |
| Posted by: rsolberg on 2016-04-18 19:18:50 I know Mathematica, Quake, and Photoshop utilize or can utilize the FPU. I believe Sim City 2000 does as well; it stopped crawling when I did the full '040 swap on my Mystic CC. | |
| Posted by: Macdrone on 2016-04-18 20:06:34 After Dark 🙂 | |
| Posted by: Guybrush3pwood on 2016-04-18 21:42:25 What about Wolfenstein 3d? Runs like crap on my 575s. | |
| Posted by: Macdrone on 2016-04-18 21:48:08 max ram and fpu will help but a boost in mhm will help the most if you can do it. | |
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