[OsakaBill]

I just installed a GigaDesigns 5D-1213G upgrade in my Gigabit ethernet PowerMac. I could not believe how fast the Mac booted. So far everything is noticeably faster. For example, I just ripped a bunch of CDs at a 25x-35x rate�|more than double the old dual 450MHz rate.

I do have a couple of questions though.

According to the information on the OtherWorld Computing website, the upgrade I bought should be using 1.2 GHz Motorola PPC 7455 chips. However, on the upgrade card, the CPUs were clearly marked as 7450. What is the implications of this difference?

Secondly, this upgrade is supposed to be 1.3 GHz and for PowerMacs with 100 MHz system bus. However, when it arrived, the jumpers were configured for either 1.0 GHz CPUs in a 100 MHz system bus or 1.33 GHz CPUs in a 133 MHz system bus. I do not understand why the jumpers were configured this way. A 100 MHz card cannot be tested in a 133 MHz PowerMac can it? And why would a 1.3 GHz card be tested at just 1.0 GHz?

Third, this upgrade came with a heat sink that included two fans. These fans are very, very loud (louder than a "Wind Tunnel" PowerMac). Is a heatsink with fans necessary? Is it normal for these fans to run loud? Can quieter fans be found and used?

Thanks for your time and assistance.

[Lateralus]

Originally posted by OsakaBill:
I just installed a GigaDesigns 5D-1213G upgrade in my Gigabit ethernet PowerMac. I could not believe how fast the Mac booted. So far everything is noticeably faster. For example, I just ripped a bunch of CDs at a 25x-35x rate?|more than double the old dual 450MHz rate.

I do have a couple of questions though.

According to the information on the OtherWorld Computing website, the upgrade I bought should be using 1.2 GHz Motorola PPC 7455 chips. However, on the upgrade card, the CPUs were clearly marked as 7450. What is the implications of this difference?

Secondly, this upgrade is supposed to be 1.3 GHz and for PowerMacs with 100 MHz system bus. However, when it arrived, the jumpers were configured for either 1.0 GHz CPUs in a 100 MHz system bus or 1.33 GHz CPUs in a 133 MHz system bus. I do not understand why the jumpers were configured this way. A 100 MHz card cannot be tested in a 133 MHz PowerMac can it? And why would a 1.3 GHz card be tested at just 1.0 GHz?

Third, this upgrade came with a heat sink that included two fans. These fans are very, very loud (louder than a "Wind Tunnel" PowerMac). Is a heatsink with fans necessary? Is it normal for these fans to run loud? Can quieter fans be found and used?

Thanks for your time and assistance.

The 7455 is just a revised 7450. Same family. All 7455s are labelled 7450.

A 100MHz card can be tested in a 133MHz machine. Most upgrades are meant to be used in 100 or 133MHz machines.

Your card was not tested at 1GHz, it was tested at 1.33GHz in a 133MHz machine. It makes more sense to test them on the 133MHz machines since the 133MHz bus is more stressful on the card than the 100MHz bus.

Just set the jumpers as you wish for your machine and be happy. Don't be afraid to set them higher, such as 1.4 or 1.5GHz. It wont damage the card and it wont void your warranty. If the processor cannot handle the 1.5GHz speed, it will either not boot up or crash. No damage. It will almost certainly handle 1.4GHz though.

The fan is very necessary, the 7455 is a hot processor. I haven't seen the upgrade in person, but I'd imagine you could replace the fans with some ease. I wouldn't recommend it yet though. If the fans are that loud, call OtherWorld or write an e-mail to their support address.