Power Mac Dual 1.8 G5

[Brother Michael]

Alright I am sure this has been brought up before...but I can't find it.

Why is the new 1.8 G5 crippled compared to the old 1.8 G5?

Mike

[King Cobra]

Piss-poor graphics cards, much worse than the previous dual 1.8 model had. I don't really care about it (luckily), but I'm sure that others that are/were fumed by the graphics card downturn would be more than happy to fill you in on the other details.

With that being said: The specifics on Apple's website say: "NVIDIA GeForce FX 5200 Ultra with 64MB DDR SDRAM" - also true for the new dual 2.0GHz model.

[keysersoze]

Piss-poor graphics cards, much worse than the previous dual 1.8 model had. I don't really care about it (luckily), but I'm sure that others that are/were fumed by the graphics card downturn would be more than happy to fill you in on the other details.

With that being said: The specifics on Apple's website say: "NVIDIA GeForce FX 5200 Ultra with 64MB DDR SDRAM" - also true for the new dual 2.0GHz model.

4 RAM slots, down from 8.

[keysersoze]

Piss-poor graphics cards, much worse than the previous dual 1.8 model had. I don't really care about it (luckily), but I'm sure that others that are/were fumed by the graphics card downturn would be more than happy to fill you in on the other details.

With that being said: The specifics on Apple's website say: "NVIDIA GeForce FX 5200 Ultra with 64MB DDR SDRAM" - also true for the new dual 2.0GHz model.

Same old 970 processor, at this point. Not the new 970fx which is shipping in the higher end models.

[Brother Michael]

errm...lemme rephrase this one...what was the reasoning behind it?

Too good of a computer for the price?

Mike

[paxtonandrew]

With the release of the 2.5 ghz G5, there needed to be a low end model to replace the outgoing 1.6ghz, so apple took the logical idea of downgrading a once middle end G5 to a low end. Not to say there is nothing wrong with the computer (and there is nothing wrong with the computer, but with the lack of Ram slots and PCI/X slots, the computer would be good for a fast family computer, or slow graphics computer. If you were to buy one, I would look at the Rev A. systems, as they have similar additions as the current 2.0 ghz models.

Hope this helps

[Brother Michael]

With the release of the 2.5 ghz G5, there needed to be a low end model to replace the outgoing 1.6ghz, so apple took the logical idea of downgrading a once middle end G5 to a low end. Not to say there is nothing wrong with the computer (and there is nothing wrong with the computer, but with the lack of Ram slots and PCI/X slots, the computer would be good for a fast family computer, or slow graphics computer. If you were to buy one, I would look at the Rev A. systems, as they have similar additions as the current 2.0 ghz models.

Hope this helps

Yea, I was looking at an older one simply because the new one looks like it is less than good...

However, due to the whole idea of money and that fact that I do not have a lot of it...I will probably get a single 1.6 G5...as they go for about 1500 now.

We shall see.

Mike

[alexf]

Same old 970 processor, at this point. Not the new 970fx which is shipping in the higher end models.

Do all of the Rev. B 2.0 GHz machines have the 970fx, or does only the 2.5 GHz have this newer chip?

Also, how can one tell which chip one has in his/her computer?

[alexf]

Piss-poor graphics cards, much worse than the previous dual 1.8 model had. I don't really care about it (luckily), but I'm sure that others that are/were fumed by the graphics card downturn would be more than happy to fill you in on the other details.

With that being said: The specifics on Apple's website say: "NVIDIA GeForce FX 5200 Ultra with 64MB DDR SDRAM" - also true for the new dual 2.0GHz model.

No, actually I believe that the new 1.8 GHz Dual kept the same graphics card but the 2.0 GHz model was downgraded.

[Sun Baked]

Do all of the Rev. B 2.0 GHz machines have the 970fx, or does only the 2.5 GHz have this newer chip?

Also, how can one tell which chip one has in his/her computer?Only the 2.5GHz machine had it initially, the Japanese Apple Marketing guy set the record straigh at the beginning -- but I just saw the translation recently.

The 2.0GHz machine just started showing up with the 970fx, the 1.8GHz machine is an unknown.

Here's the scoop, mainly it's the lack of the HT PCI-X Tunnel that makes the machine different from any other -- the old SP1.6 PM had the HT PCI-X Tunnel, but used resistors on the motherboard to keep the HT PCI-X Tunnel at PCI speeds (considering some SP1.8PM boards were shipped as SP1.6PMs).

http://forums.macrumors.com/attachment.php?attachmentid=15146

So you cannot play with the resistors to boost the speed of the PCI on the new DP1.8PM machines. :(

[alexf]

Thanks for the reply and the diagram...

I happen to have a 1.6 GHz machine. Does that mean that I can play with the resistors and increase the speed?

[Sun Baked]

Thanks for the reply and the diagram...

I happen to have a 1.6 GHz machine. Does that mean that I can play with the resistors and increase the speed?Probably, depends on who made the HT PCI-X tunnel.

If it's the AMD-8131 (pdf) (http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/24637.pdf)...
If the systemboard supports PCI-X mode operation for a bridge, then a pullup resistor to VDD33 must be placed on the bridge’s PCIXCAP pin. To limit the frequency of a PCI-X-capable bridge to 66 MHz on a systemboard, the systemboard must also include a pulldown resistor from the bridge’s PCIXCAP pin to ground. The strapping options on GNT[4:3]# are used to distinguish between systems that support 100MHz and 133 MHz; in either of these two cases, the system board should include no pulldown resistors on PCIXCAP.

[keysersoze]

Also, how can one tell which chip one has in his/her computer?

Courtesy of Shadowband:

1) bring up a terminal window (Applications/Utilities/Terminal)
2) enter the following:

ioreg -l | grep cpu-version

A CPU version of <003c0300> equates to PowerPc 970fx rev 3
A CPU version of <00390202> equates to PowerPc 970 rev 2.2

Note: two entries will be output since rev b powermacs are all DP.

:)

[alexf]

Thanks Keyserzose :)