Recent content by hoi polloi

Did you have any luck with this? I found a dual 800MHz quicksilver CPU card to play with.  I swapped in a couple 7455B chips and it's working now at 1.2GHz with the 2MB L3 cache.  The 7455B chips are much better than the original 7450.  They're both faster and cooler at a lower voltage.  This...

I was able to make some progress on this.  It is possible to enable the L3 cache after boot.  This is a 733MHz 1MB L3 DA card that I swapped the CPU and cache chips, and removed the flash chip so that it would boot:

If you can read them, can you also write them?  The best result so far is the one in the first post, which is using the flash chip from a 1.25 MDD single with 1MB.  As you can see, it runs at 6x, and I've been able to get this card to work at 1.6GHz with the original 1MB cache chips.  That takes...

What is the latest on this?  Were you able to repair or replace the PSU?

Do all of those ports work?  The firewire chip looks a bit corroded. At least it looks like you got a nice CPU upgrade with it!  Which one is it?

Could it be the power supply? 

What do you mean by 'regulator' on the VRM?  The VRM is a DC-DC converter that takes 28v in and puts out 3.3, 5 and 12v.  Usually a 'regulator' does this same thing for low power applications because it's inefficient (heat).  I've replaced these VRM FETs with new ones a few times.  There are...

The chip is a little 8-pin surface mount part marked 3402W.  Just about any G4 CPU card with cache chips will have one.  Even the 350MHz 7400 cards. I've had some luck transplanting these chips, but I get some weird behavior.  I installed some 2MB cache chips, thinking it would work with the...

I don't suppose anyone here is able to flash these chips?  It's frustrating to be able to re-solder 600 connections and then get stopped by software.  This is the same issue with using the 7448... I discovered that if I remove the flash chip the machine will boot without L3 enabled.  Is there a...

Thank you for replying; that is some great info! So how are you reading/writing that flash chip?

I've been tinkering with a BGA-swapped CPU card and I've had difficulty getting it to run at speed because of the L3 cache ratio.  The original 733MHz CPU works with a 4:1 ratio, but the 1400MHz chip needs 6:1.  Does anyone know how to set the L3CR register at or before boot time?  I suspect...

OSX definitely knows when it has dual CPUs.  Even if a particular app isn't written for it, I've had better overall productivity on duals because I usually have multiple programs going.  Here is one of the comparisons I remember seeing: https://barefeats.com/pm05.html He has done a few similar...

Pull up activity monitor or run top, etc.  It should be pretty clear what's going on.  As I said, geekbench is not a good benchmarking tool.  Anything, and I mean any--thing, else running will lower the score.  Try safe booting, for example...

Just run it again; you'll get a different number.  It's pretty bad software for benchmarking.