Someone sent me some 7448 chips to install, and I can report that they also work fine on these boards with the 7400 adapters. The Powerlogix/Newer Technology patch works to fix the firmware on machines that use these boards.
Thanks for sharing your results!
I was tinkering a bit with a 7410 in a Pismo and tried it at 1.6v and 500MHz. It was happy with these settings and cool running. I also tried 1.5v, but that was too low for stable operation once it got warm. So one more data point... ymmv.
I added data for the 256KB setting. This plot also shows another way to look at the same data. With zero L2 cache as the baseline, this shows the speed increase with different amounts of cache added. So it's like looking at the performance hit for not having the cache, or the performance gain...
This shows testing with sorting arrays of integers. The size of the arrays increase: 16KB, 32KB, 320KB, 3.2MB, 32MB, and 64MB. The plot shows sorting speed relative to results with 2MB of L2 cache. You can see that less cache is always slower, but there is a range of array sizes where the...
On the G4 CPU, the external memory cache is configured with a register. In the following example a 600MHz 7400 CPU has an actual 2MB of L2 "backside" cache physically existing in hardware, but reduced amounts of 1MB, 512K, and zero L2 cache can also be set in software. This picture is showing...
I think some of the reported L3 issues are firmware or power-saving related. Maybe some of the firmware experts could figure out the details of what it's doing, but I think the later Titaniums would turn off L3 when on battery, or when in "reduced" performance mode. The CPU speed and voltage...
The manual is available from here:
http://www.sonnettech.com/support/downloads/manuals/encore_st_1800_qsg.pdf, among a variety of other places.
In there it has information related to the problem you have described:
This problem is well documented for a range of aftermarket G4 CPU upgrades...
Hello, welcome to the forum. Sonnet is still around and supports their products. The search function on this site is pretty good too.
http://www.sonnettech.com/support/kb/kb.php?cat=582
I always liked this CPU benchmark:
https://www.math.utah.edu/~mayer/linux/bmark.html
That's nbench, which is derived from BYTE Magazine's BYTEmark benchmark program. It has a long history with results from a wide variety of machines over the years. That implementation compiles on 'nux, but...
I have not yet tried to install a 7447 into a G3 machine, but in theory it should be possible. The Pismo may be my first attempt. There is some preliminary discussion of that in this thread:
68kmla.org/bb/index.php?threads/550mhz-g4-powerbook-pismo-vs-titanium.45851/
As others have...
A 7448 should work fine (or better) anywhere that a 7447 can, but I don't know where to get them. New 7447 chips are for sale on ebay.
Amazingly, documents like this are available, even today:
www.nxp.com/docs/en/application-note/AN1812.pdf
In there you can see that pin-compatible chips are...
Thanks for the reply LightBulbFun. I don't suppose you have a schematic for anything with a 750L, 7400 or 7410 CPU?
I think a G3 chip could be installed on a GigE CPU board that came with a 7400, but I have not tried it. If you check those same pins on one of those boards you might even...