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waxcrash · Sep 15, 2005, 10:52 AM

Currently, the fasted processor upgrade available is a dual 1.8GHz. Do you think Giga Designs or Sonnet will eventually release a dual 2GHz upgrade?

Lateralus · Sep 15, 2005, 10:56 AM

Yes.

The successor to the 7447A G4 that is used in all of the current G4 upgrades is already in the channel, dubbed the 7448. It is supposed to be coming in with a rated speed of 1.7-1.8GHz and will produce less heat than the 7447A. And with heat having been the main barrier in getting Dual 2GHz models from the 7447A crop, I have little doubt we'll get at least Dual 2GHz from the 7448s. I'm banking on Dual 2.13GHz, actually.

The 7448 also offers a few other goodies, namely a doubling of the L2 cache to 1MB which should yield a 10-20% performance boost over the 7447A at the same speed. The AltiVec engine has also been tweaked a little bit to support 'ECC', for correcting code errors. It should result in a boost in performance for AltiVec code on the whole, but nobody seems to know how much though.

Pickings of GigaDesigns' 7447A upgrades seem to be getting kinda slim as there aren't many in the channel. So either Giga is having supply problems, which I doubt, or they're allowing the 7447A supply to dwindel down before releasing 7448 upgrades. Which makes sense since the timeframe for 7448 upgrades to hit was this fall.

Give it a month or two I'd imagine.

hotani · Sep 15, 2005, 11:02 AM

Sweet. I'm waiting......

Actually I haven't seen anything for the MDD for a while- it vanished from giga's site, but IIRC that one was dual 1.3GHz or something. If a dual 2GHz came out I think i'd finally bite the bullet....

OreoCookie · Sep 15, 2005, 11:32 AM

Since Powerlogix offers single 2.0 GHz G4 upgrades for around $370, I think it's just a matter of supply constraints and price to release such an upgrade card (a dual 1.8 GHz sets you back about $600 already, a bit less than twice as much as a single-cpu upgrade card).

Lateralus · Sep 15, 2005, 11:44 AM

No, it's heat.

I've had a good deal of correspondance with Giga on this. Due to the size constaints of not only the PCB which the CPUs are housed on, but the G4 case itself, the cooling solution can only be so large. It is adequate for cooling a single 2GHz processor, but not two. There was a bit of hesitation in releasing even the Dual 1.8GHz model.

And a Dual 1.8GHz upgrade can be had for $470, not $600.

hotani · Sep 15, 2005, 12:38 PM

Originally Posted by Lateralus

And a Dual 1.8GHz upgrade can be had for $470, not $600.

For MDD? *pulls out credit card....*

OreoCookie · Sep 15, 2005, 01:39 PM

Originally Posted by Lateralus

No, it's heat.

I've had a good deal of correspondance with Giga on this. Due to the size constaints of not only the PCB which the CPUs are housed on, but the G4 case itself, the cooling solution can only be so large. It is adequate for cooling a single 2GHz processor, but not two. There was a bit of hesitation in releasing even the Dual 1.8GHz model.

And a Dual 1.8GHz upgrade can be had for $470, not $600.

I took the prices from the website I quoted. (German prices are entirely different, and I don't have experience finding the cheapest offer.)

What kind of coolers do they mount on them? Copper or copper core with aluminum cooler?