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Sonnet's Cresendo L2/G3 Review
for the 5400/6400

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Click here to read Craig's Sonnet 400/1M install review

Sonnet L2/G3 image

Well it didn't take to long before us 6400 users got a choice in G3 upgrades. Sonnet has released 3 versions of its popular Cresendo line of G3 upgrades that will run in a 6400 or similar mother board. These G3 upgrades fit in the L2 cache slot just like Vimages does, but this is about as far as the similarities go.

Sonnets line consists of a:
240/250Mhz G3 with 512k L2 cache for $399
300Mhz G3 with 512k L2 cache for $499
300Mhz G3 with 1M L2 cache for $599

You may notice that the 240Mhz version also runs at 250Mhz. This setting is for systems with 50Mhz bus speeds such as the 6500 or TAM. The 300Mhz cards will run at 300Mhz in any system. You will also notice the very large PURPLE heatsink. This is Sonnets strategy for making these L2 G3 cards more compatible with higher speeds in a larger array of systems. The size of the heatsink helps cool the CPU down much more than the smaller heatsink on Vimages G3 which allows Sonnets to run in a TAM with no fan (which will take up one of your RAM slots). Also they can run higher clock rates without over heating the CPU. I'll get back to this point later. Also at this time, Sonnet is the only one selling a 300Mhz version. Both Vimage and Newer are expecting a 300+ Mhz G3 upgrade in the near future. In fact the only system Sonnets L2/G3 won't work in is the UMAX C500 due to the large heatsink so UMAX C500 owners will have to stick with Vimages G3.

Sonnet has also cornered the price market as well with the 300/1M G3 topping off at only $599, now we all can afford a high speed G3. This was the one I was most anxious to test and Sonnet was nice enough to send all 3 so hold on and get ready for this trio of speed. The kit includes the installation manual, floppy disk with the Cresendo driver on it, a sticker to place on your case, and of course the G3 card.

Sonnet kit image

The installation manual consists of a 1 page Xerox copy manual for each system including pictures for reference. This was all that was needed because it's pretty straight forward installing a card in your L2 cache slot. The sticker which says "Powered By Sonnet, Simply Fast" is a nice touch! It reminds me of my drag racing days :)


The Cresendo L2/G3 comes in the choices listed above. The L2 cache of each runs at 1/2 the CPU speed so the 240/250 cards cache runs at 120/125Mhz and both the 300 cards caches run at 150Mhz. As with Vimages card, they will not interfere with any PCI card but The large heatsink will just touch RAM modules with chips on both sides. This is usually the case with large capacity RAM such as 32M or 64M DIMMS. Sonnet says this will not harm anything and I found this to be true. It does touch the nearest RAM DIMM in both of my 6400's with no side affects. If anything its probably cooling the RAM chips as well :) You can see from the picture below just how large Sonnets G3 card is compared to Vimages and a standard 512k L2 cache. NOTE: the picture of Sonnets card was cut off by my camera so I had to reproduce the upper two thirds with Adobe Photoshop in order to show this picture. Makes me wish I had a digital camera :)

L2/G3 comparison image
Sonnet Cresendo 300/1M L2 G3
Vimage Vpower PF 240 G3
Sonnet 512k L2 cache


Just as with any other L2 cache, Sonnets L2 G3 cards install just as simple. First you install the software from the floppy disk. This includes The Cresendo extension, Metronome Apple Menu item, and LibMoto extension. Then you power down the Mac and the rest is just like adding a L2 cache (The following is for the 6400 but you will find instructions for all other compatible models in the manual). You will need a Phillips screw driver, the G3 card, and a magazine. Before removing the power cord, touch the metal covers for the PCI slots to ground yourself and try not to move after this point (computer electronics don't like static electricity!)

Rear of 6400

Now remove the 2 screws that hold the motherboard in, then carefully pull out the board. Place it on the magazine so you don't damage the components on the back. If you have a L2 card already installed, it will be necessary to remove it before inserting the G3. I found it easy to remove the L2 cache by using a small flathead screw driver (like a jewelers screw driver). I put it under the very end of the cache card and used it to help pry it out. These cards are in very tight so you will have to use some force but please be careful! Now insert your new G3 card and here's the crucial point, you MUST press the motherboard reset button found right next to the Ram slots. If you do not do this then your G3 may not be recognized or worse your computer might crash. This is not limited to the G3 card and you should press this button when installing or removing any card from the 6400. The manual does not state this but it has been mentioned by Apple many times and is in the Performa 6400 User manual. Now just put your mother board back in and your done. Your now ready to experience G3 speed!

Sonnet L2/G3 on MB image

You can see how close the heatsink is to my RAM chip. They are touching.


Now was the time to see how they work. I started my 6400 and it booted right up and loaded the Cresendo extension in alphabetical order so you have to wait for a few extensions to load before the G3 kicks on but when it does you know! This guy does not have to reboot! Yes it actually gets to the Cresendo extension, fires up the G3 and keeps on going. Vimage users all know that the wait for the reboot can be a drag sometimes. Sonnet added the same saying under the Mac splash screen as the sticker has which is another nice touch :) I saw no screen anomalies or anything peculiar at all. Looks like Sonnet has one up on the competition. After boot your desktop will rebuild itself because Sonnet installed a small extension that deletes itself to force this. I don't know why, but they did? One of my 6400's didn't come through the rebuild ok and I had to re-rebuild the desktop due to many generic icons. My other 6400 had no problem with the rebuild? since we pressed the mother board reset button it will be necessary to reset your Date & Time control panel so now is a good time. After I did this I went straight to the Metronome App in the Apple Menu to see if everything was OK, and it was.

Metronome image

The image above is displaying the readout of the 240Mhz G3. Its nice that they displayed the temp too. Vimages Vpower Info app does not. The 300Mhz G3's actually run cooler and I'll get to that later. Also your window border won't look the same because I have the Gizmo Theme running in OS 8.5.1.


Now comes what you all have been waiting for. I ran benchmarks using MacBench 5.0 with all 3 cards plus my 6400/180 with no L2 cache, 512k L2 cache and Vimages 240 G3 for comparison. Well this is what you all wanted right! Right. Here is my systems configuration.

I'm only displaying the one 6400 because scores were almost identical with my 6400/220 and Sonnets G3 except for disk which was much faster due to my 5.7G Maxtor HD.

MacBench 5.0 Scores
MacBench 5.0 scores image

As you can see Sonnets G3's make about a 3X to almost 5X improvement in CPU and FPU from my 6400/180 with no L2 cache. The disk scores increased by a little more than 1/2 but you can see how it maxed out with all being about the same. This is due to the capability of the HD that Apple bundled in the 6400. Oh Well. My Maxtor drive got a score of 1000% which shows how much better it is! Sonnet claims that their G3's are faster in FPU then Vimages because they bundle LibMoto which accelerates FPU calculations. Vimage does not bundle LibMoto with its G3's but I ran MacBench with it installed just to see how it would do. It fell right in line with Sonnets 240Mhz card as I expected. LibMoto is a free download from Motorola so Vimage users can benefit from it as well.

Application Launch Times
603e 180/0k Sonnet G3 240/512k Sonnet G3 300/512k Sonnet G3 300/1M Vimage G3 240/512k
Boot Speed 1m 53s 1m 35s 1m 35s 1m 32s 2m 4s
PhotoShop 4.0.1 17s 8s 7s 7s 8s
Corel 6 15s 8s 7s 6s 8s
Word98 15s 9s 7s 7s 9s
AOL 4.0 Preview II 19s 11s 10s 9s 10s
Netscape 4.0.5 14s 8s 6s 6s 7s
RealPC 1.0.4 3m 10s 1m 33s 1m 19s 1m 20s 1m 35s
Speedometer 16bit graphics test 1.206 2.650 2.629 3.167 2.431
CPU temp after test completion N/A 51c 35c 27c 75c

From the scores above you can tell just how much faster a 6400 can be with any speed G3 installed. All boot times are faster except for Vimages which has to do the reboot, but its only 11s slower than no G3 at all. There doesn't seem to be much difference in application launch times due to the HD being pretty much maxed as I mentioned before. Launching RealPC on the other hand show what a faster G3 can do because its much more processor intensive. But even here my Maxtor HD with Sonnets 300/1M G3 launched it in 58s! That's 1/2 a minute faster then booting Mac OS 8.5.1. Wait, I'm praising the wrong side! Eh hmm. That would be a fully loaded MacOS 8.5.1. Now that's better :) You don't really see the speed of the 300/1M until you run apps. It really is much snappier than the others. I tried playing Grand Turismo on Connectix's Virtual GameStation and it does play with the 300/1M card but is too choppy with any slower model. I only have a Rage II which is the minimum requirements but a Rage Pro or Rage 128 may just make the slower G3's play it at a descent speed. For comparison my PB G3/233 plays Grand Turismo with almost no glitches at all compared to my 6400's. It has the Rage Pro but I think the 66Mhz bus has more to do with it. RealPC gets even more life like with the 300/1M card also. Windows is very snappy and games become much more enjoyable.


You may have noticed that the faster the G3 card was the cooler the temp readings were? Sonnet is using non-copper CPU's in the 240/250 card and copper CPU's in the 300 cards. Sonnet was hesitant at first to admit this but they finally did and I think the reason is the FAQ posted on Vimages web site. In plain english, it states that a non-copper 300+ Mhz G3 will not last in the 6400's case due to heat issues and will fail over time. When Sonnet first advertised their intentions of selling a 300Mhz L2/G3 for the 6400 at only $599, many believed it would have to be a non-copper CPU due to the low price. This conflicted with Vimages FAQ which Sonnet clearly stated can work due to their over sized heatsink. Now I'm no semiconductor engineer but I do know that as CPU speeds increase so does heat dissipation unless something else is changed. All 3 cards have the same size heatsink so what else? The CPU. They are using copper based G3 chips at this time but told me that they tested their cards to run with or without a copper CPU and have no side affects. Now this makes sense as all temp readings I have ever seen for copper CPU's are around 23c to 40c. I only hope that they are right about the non-copper CPU's running OK if they ever switch back? I would buy one now while their still using copper CPU's. If you want to see just how well the heatsink really is working then just look at the temp readings for both Sonnets 240 G3 and Vimages 240 G3. Sonnets is practically 25c cooler which is why it works in more systems without interfering with other components. I did try putting more heatsink compound and placing the fan on the edge of Vimages card which brought the temps down but not as low as Sonnets.

Now is the time for fun! As with all speed enthusiasts, I wanted to make my new G3's even faster. I first tried moving the Cresendo extension to the front by placing a space in front of it and then installed PowerLogix Cache Utility setting the cache to 200Mhz. This was a big mistake! I crashed several times at boot before it finally made it all the way. When I ran MacBench, I only gained a few points. My startup was 20s faster when it finally worked but my HD had taken a beating. I had to run Norton DiskDoctor five times to clean up the mess. Others have ran the cache utility with minor issues but not me. Although I don't know if I can put all the blame on the speed of the cache as Sonnet just released an update to the Cresendo extension due to crashing issues at bootime. This new extension does not crash my computer but I'm very hesitant to using the cache utility again?


Here is where Sonnets cards shine. In a word there is NONE! Sonnets L2/G3 has no issues with any devices as of the Cresendo 1.3.4 release. They did have an issue with crashing at boot but this new extension is supposed to fix that. There has been no reports of issues with any graphics or SCSI cards so all you IXMicro owners will be happy! It works with OS's 7.5.3 thru 8.5.1 with or without VM and works with the Geo modem in all compatible OS's. I personally noticed nothing wrong at all with my ATI VR Rage II or Geo modem. It also works in Power Computings PowerBase line which is based on the 6400's mother board, Vimages does not. And as of a few weeks ago, the same G3 cards will work on both 6400's and Apples 4400 or Motorola StarMax systems which makes this card very universal. One card for all similar systems! As I mentioned earlier, the only system in which this card will not work is the UMAX C500, so these owners will have to stay with Vimage or see what Newer comes out with?


You know I didn't think it could be done, but Sonnet has WOWed me again! These cards are very fast and stable. Some did have issues with boot crashes and I will admit I had a few but the updated extension seems to have cleared this for me. And who can complain about the price! I know that you've probably read other reviews stating that an iMac may be more suitable for the price but who are they kidding. At $599 for the 300/1M plus lets say an even $600 if you were to sell your 6400, is about what a new 266Mhz iMac would cost. So unless you never touched the inside of your 6400 and its all still stock, these G3's are perfect for you. But even the slowest G3 at $399 will spruce up that stock 6400. And with an iMac your stuck. You'll never get that new ATI Rage128 to run in it :)

Update 4/9/1999, I kept a Sonnet card!: Well, I couldn't help myself. I actually kept the 300/512k Sonnet card and returned the other 2. I was getting tired of the double boots the Vimage card does on my 6400 with the 2 monitors (it takes so long for the monitor on the ATI card to re-sync) so I decided to keep one of Sonnets. I figured the 300/512k was a good choice due to it being cheaper then the top of the line but faster then the 240 card I had. I am expecting to get a new G3, or perhaps a G4, before the years end so I didn't want to spend a lot of money on my 6400 right now.

Update 6/10/1999, Sonnet may not be the best choice!: Ok, I may eat my words on this but I have been getting some massive crashes since installing OS 8.6 and running the latest 1.3.6 Crescendo drivers. Sometimes it takes 3 boots before my computer will complete to the Finder! This is outrageous! I got so fed up that I removed it and replaced the Vimage card. Now everything is ok so I guess I have to live with the double boots. It seems the better choice may be Vimages as long as you don't have one of the incompatible video cards. If so, then Sonnets is your only choice. I still have Sonnets card in my other 6400 for testing purposes and hopfully Sonnet will fix these issues!

Update 2/11/2000, Well Sonnet made it better finally!: Ok, I am chewing a bit on my words. Mmmmm tasty :) Anyway with the release version 1.4.1 of the Crescendo driver Sonnet has been able to rid us of the boot crashing! I also have heard that OS 8.5 or later is needed to fix issues with audio clipping and causing crashes. This part is not entirely fixed but much improved. So Sonnet is back on the OK list again :)

Sonnet Technologies, Inc.
18004 Sky Park Circle
Irvine, CA. 92614-6428

Voice (949) 261-2800 Fax (949) 261-2461
email: sales@sonnettech.com

Check out my Sonnet Info page for more info

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This page last updated 4/6/2000