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Kirathus · Dec 29, 2005, 01:13 PM

So... I think im going to splurge and buy a desktop...

Which one!?

(A). Refurbished PowerMac Dual Proc 2x 2.7 GHz ($2300)
(B). New PowerMac Dual Core 2x 2.0 GHz ($2200)
(C). New iMac Single Proc 1x 2.1 GHz ($1800)

Going by the Macworld Lab Tests... the 2.7 is the way to go... But do those PowerMacs really compare THAT much over the iMac 20" ???

They ARE... All very very sexy.

Benefits of (A) over (B):

Shear processing power
Faster FSB

Benefits of (B) over (A):

DDR2@533 memory
Twice the cache
Dual Layer Superdrive as opposed to regular.
PCI express graphics over AGP

Benefits of (C) over (A) and (B):

monitor included
much cheaper

Amorya · Dec 29, 2005, 01:33 PM

I had the same choice, and went for B. It's serving me well

KSE7696 · Dec 29, 2005, 01:33 PM

I would jump on the 2.7 G5 deal if I had the extra money.

Kirathus · 01:47 PM

I am really leaning toward option (B) right now...

Lateralus · Dec 29, 2005, 01:45 PM

Agreed. The Dual 2.7 is going to be significantly faster.

And as for the SuperDrive; Sell the stock drive on eBay as 'Genuine Apple' and somebody will pay upwards of $70-80 for it. Then, head over to NewEgg and buy a Pioneer DVR-109 or 110 for $40. Same drive that's in the current models.

And in regards to DDR2; DDR2 has a higher latency than DDR, so in order for there to be an appreciable speed boost, there would need to be a pretty big clock speed difference. DDR 400 and DDR2 533 perform pretty comparably. In order to see a real difference with DDR2, you'd need to step it up to 667.

Also; the Dual 2.7 has 2.7GHz of bus bandwith through two 1.35GHz busses, one for each CPU. The Dual-Core 2.0 shares one 1GHz bus.

Al G · Dec 29, 2005, 03:37 PM

The Dual 2.7 comes with a DL Superdrive.

Kirathus · Dec 29, 2005, 04:29 PM

Originally Posted by Al G

The Dual 2.7 comes with a DL Superdrive.

really? the refurb one?

Kirathus · Dec 29, 2005, 04:42 PM

hehe, i see... very nice.

G5man · Dec 29, 2005, 04:46 PM

There are no Dual 2.7's in refurbished stock. There are dual 2.5's though. What will you be using the G5 for?

Kirathus · Dec 29, 2005, 04:54 PM

yeah there are

take a look at store.apple.com and click apple certified.

as far as its use...
it is to be my primary computer. it will be used for image/video editing, software development, web development, and... hehe... gaming.

oh yeah... and... i am a Computer Science student... soo... regular student stuff too... not that that makes a difference...

G5man · Dec 29, 2005, 05:14 PM

Oh whoops, I usually run a search "Apple Refurbished". For your stuff that you do you are deffinatly going to want a PowerMac. Do you plan to upgrade the machine in the future? or will configurations stay the same? What displays are you planning on using?

Kirathus · Dec 29, 2005, 05:19 PM

upgrades may happen in the future... but i hope not for at least 2.5 years...

my only display will be a 17" CRT analog and a 15" LCD digital.

G5man · Dec 29, 2005, 10:19 PM

This is tough, RAM upgrades would be needed immediatly for sure, third party RAM is best for price. It is hard to decide because you do not want to upgrade the machine for 2 and a half years and then it when the Intel machines come, meaning that the PCI X maybe obsolete, along with all the old interfaces. Very tough decission.

mduell · Dec 30, 2005, 01:11 AM

I'd try the iMac (either in store, or 13 days after you buy it). If it's not fast enough then get the dual 2.0 if you want upgraded graphics or PCIe (video input/output, drive controllers, etc) in the future or the dual 2.7 if you are happy with what's available now.

Originally Posted by Lateralus

And as for the SuperDrive; Sell the stock drive on eBay as 'Genuine Apple' and somebody will pay upwards of $70-80 for it. Then, head over to NewEgg and buy a Pioneer DVR-109 or 110 for $40. Same drive that's in the current models.

And in regards to DDR2; DDR2 has a higher latency than DDR, so in order for there to be an appreciable speed boost, there would need to be a pretty big clock speed difference. DDR 400 and DDR2 533 perform pretty comparably. In order to see a real difference with DDR2, you'd need to step it up to 667.

Also; the Dual 2.7 has 2.7GHz of bus bandwith through two 1.35GHz busses, one for each CPU. The Dual-Core 2.0 shares one 1GHz bus.

Good idea with the DVD burner. He could do the same with the RAM.

The RAM itsself has the same minimum latency (4 cycles at at 533Mhz is the same as 3 at 400Mhz) but they may have revamped the memory controller to improve latency (it was pretty bad before).

In what app/task does the FSB difference (instead of just the clockrate difference) create a nontrivial difference?

Lateralus · 01:33 AM

Now? I don't think there are any apps. For me, it's simply a matter of knowing that there's no bus contention going on.

And total bandwidth will come into play in the future with processor upgrades. When bus multipliers increase with future CPUs, the bus bandwidth will indeed become more critical. And I know you seem quite certain that there will never be G5 upgrades, but I beg to differ. There are very, very few desktop Macs from the 601-G4 era that do not have some sort of processor upgrade available for them, some of which were designed from the outset by Apple to prohibit processor upgrades. And more than that, Sonnet has said publicly that they're working on G5 processor upgrades.

mduell · Dec 30, 2005, 01:51 AM

Originally Posted by Lateralus

And total bandwidth will come into play in the future with processor upgrades. When bus multipliers increase with future CPUs, the bus bandwidth will indeed become more critical. And I know you seem quite certain that there will never be G5 upgrades, but I beg to differ. There are very, very few desktop Macs from the 601-G4 era that do not have some sort of processor upgrade available for them, some of which were designed from the outset by Apple to prohibit processor upgrades. And more than that, Sonnet has said publicly that they're working on G5 processor upgrades.

On some of those models where Apple tried to prevent upgrades, the upgrade companies had to go to PCI cards; putting a G5 in a 250Mhz/2GBps PCIe slot (or worse, a 33Mhz/.3GBps PCI slot or 133Mhz/1GBps PCI-X slot) isn't going to work so well. And then you have to deal with all that heat (look at Apple's current cooling solution, now try to fit that in the PCI bay).

I hope Sonnet/PowerLogix/Newer Tech/FastMac can make upgrades work, but I'm not optimistic. If they can get upgrades for the sockets (which is the only real option in my opinion), there's no saying that the FSB can't be increased (i.e. we don't know that the system controllers are only capable of the FSB they ship with).

Lateralus · Dec 30, 2005, 01:59 AM

My point in referring to past machines was that CPU upgrades are always developed, even when the CPU isn't replaceable. In the case of the G5, it does have a socket interface. So the only things holding back processor upgrades, really, are the development of a PCB versatile enough to support a range differently clocked CPUs, and the fact that up until the release of the 970MP, there had not been enough of a speed boost within the G5 family to warrant the pursuit of an upgrade, for consumers of for manufacturers.

That said, I've heard more than once that Apple used Dual 2.5GHz/PCI-X machines as test beds for the Dual 2.5GHz/PCIe processor cards during development. Which is promising to say the least.

As for increasing of the bus speed, I have my doubts. As far as I know, the G5 boards are not identical acrosss models and are locked into a specific bus speed. People have tried putting 1.8GHz/900MHz cards into 1.6GHz/800MHz systems with no luck. But, we'll see.

Sirfishalot · Dec 30, 2005, 05:06 AM

I was looking at the 20" iMac also, but I didn't like the fact that it would be difficult to swap out the hard drive or video card. Plus I ran some Photoshop filter tests where the Powermac clobbered the iMac. Oh yeah and I really like the idea of being able to have 16 Gigs of RAM.
I ordered my Dual this evening.

Jay

doublep · Dec 30, 2005, 06:40 AM

Tough choice... Personnally, I would go for A because of the faster clock speed.

Kirathus · Dec 30, 2005, 07:48 AM

Lateralus, what do you think?

jamil5454 · Dec 30, 2005, 10:51 AM

I would personally go for the iMac. It's got so many cool features, and it's not slow at 2.1 Ghz. Would be perfect for a student.

Lateralus · Dec 30, 2005, 12:57 PM

Originally Posted by Kirathus

Lateralus, what do you think?

If you've got a monitor, or have enough money to get a tower and a monitor; The Dual 2.7.

Todd Madson · Dec 30, 2005, 02:54 PM

Go for the 2.7. That's what I would do anyway.

Let me tell you, I'm thinking that in the future I will never buy a computer
again without dual processing or dual core capability. That makes more of
a difference to me in a way than the extra speed - every computer I've
touched since I bought my dual has periods where the single processor
architecture bogs and slows and it's incredibly noticeable after you've
used a DP or DC for a while.

The 2.0 would be nice but the 2.7 will give you extra speed - it will give
you more time to use it efficiently when Intels arrive so by the time you
are ready to retire it we might be into the 3rd generation Intel boxes.

Todd Madson · Dec 30, 2005, 03:00 PM

Another thought: I've also heard more than once that dual 2.5 systems apparently
can be made to accept quad 2.5 boards because the bus frequency is identical.

This is apparently what Apple did during testing of the quad processor boards,
they used dual 2.5 chassis with 2.5 DC test boards.

Word is in the future one of the CPU upgrade manufacturers is going to provide
a quad 2.5 upgrade for dual 2.5 owners. This might be possible for the 2.7 in
the future if they ever get the dual core 2.5 processors to scale to 2.7 ghz.

Even a DC 2.5 would be a good deal and the DVD burner can be flashed to
make it a faster dual layer burner. It's a burner that's been dumbed down.

The 2.7 machines, to my knowledge, have always had a dual layer dvd burner
in them.