SAM 460 poor performance, high price

[Louis Dias]

Those benchmarks do not flush to memory at all, they work inside the cache. The L1 cache performance numbers have nothing to do with memory bus performance.


So if we're talking about the memory performance clearly we're not interested about the CPU internal cache. Or did we again change the subject?

Aren't you the one changing the subject?

You called the SAM460 a poor performer.
Test show in some aspects it outpeforms a G4 Mac...
A G4 Mac does not even use DDR2 to my knowledge.  The memory test you posted is questional in the sense that I don't know if the memory controller in the '460 is actually running in burst mode because if it did, I would expect the memory tests to have favored it.

You then tried to blame to OS...which we know is your ultimate goal.

I pointed out that it may at some point outperform a G5 Mac on memory transfers since it used at best DDR2-533 and SAM460 *might* support faster memory (ala DDR2-800 or 1033) and also support faster video cards since is has native PCIex16 support.

So, no the SAM460 doesn't have Altivec, but it still has more than enough juice to hold it's own.

[Louis Dias]

Of course it is not. These memory speed benchmarks only allocate the buffer once, and this time spent allocating the memory is not accounted.


You're seriously confused.


If that is the case then this SAM460 has a lot more problems the issues listed so far...

If the fpga is the memory controller then it can be fixed.  This may have skewed the test to begin with and yes is limiting the OS now.  *now* but perhaps not *later*.

[Piru]

Aren't you the one changing the subject?

I think I have been quite consistent.

I would expect the memory tests to have favored it.

I think we're getting to the core of the issue here. You expected something to to be true, made a bogus claim and now are unwilling to back off and admit your mistake.

You then tried to blame to OS...which we know is your ultimate goal.

I didn't bring quake3 to this thread. I merely commented your contradictory and clearly bogus claims.

[Piru]

If the fpga is the memory controller then it can be fixed.

The memory controller is inside the AMCC460 CPU.

On-chip DDR1/2 SDRAM controller with 32/64-bit interface, up to 3.2 GBps peak data rate and optional ECC

[Louis Dias]

I think I have been quite consistent.

Opinions vary.

I think we're getting to the core of the issue here. You expected something to to be true, made a bogus claim and now are unwilling to back off and admit your mistake.

What mistake?  The Mac uses DDR1, SAM460 uses DDR2.  @ 400 rating DDR1 will outperform DDR2 at the same rating because of latency and overhead.  If SAM460 can use memory faster than DDR2-400 then it will outperform the G4's DDR-400 memory.  These are facts.

From the source I didn't see what memories were used.  From the results, it looks like we are comparing DDR-400 to DDR2-400.

Let's see what happens when faster memory is used in the SAM, shall we?

I didn't bring quake3 to this thread. I merely commented your contradictory and clearly bogus claims.

I didn't bring it into the thread either and wasn't replying to you on it.  I still stand by the fact that the bulk of the processing is due to the work done on the gpu.  You can look at MacOS running Quake 3 and see that on the same hardware it's twice as fast as MOS.  So while yes the driver is not good on OS4, it's still not perfect on MOS and that to see an improvement in the actual video card used will still result in a direct improvement of the framerate more than a mild improvement in the PCI bus.  You simply just spun that into another reason to bash OS4 where as the poster was curious as to what to expect with OS4's Quake 3 port on SAM460 over the SAM440...

[Piru]

If SAM460 can use memory faster than DDR2-400 then it will outperform the G4's DDR-400 memory.  These are facts.

According to Applied Micro the AMCC460 does max DDR2-400 (peak speed 3200 MB/s). Mac mini G4 uses 166MHz bus though so DDR-333. That evens up the situation a bit, but for some reason Mac mini G4 still is faster.

You can look at MacOS running Quake 3 and see that on the same hardware it's twice as fast as MOS. So while yes the driver is not good on OS4, it's still not perfect on MOS

Until RadeonHD has 3D drivers the whole question of Quake 3 performance is academic anyway.

And just as a final remark the work in progress MorphOS 3D drivers already run Quake 3 faster than Mac OS X.

[yakumo9275]

I pointed out that it may at some point outperform a G5 Mac on memory transfers since it used at best DDR2-533 and SAM460 *might* support faster memory (ala DDR2-800 or 1033) and also support faster video cards since is has native PCIex16 support.

in actuality, its a 4x pcie-lane, and once you take protocol overhead out of the 4x lane, it pushes the same amount as the macmini agp 4x slot. so any of the g4/g5 macs that have an agp 8x slot can push more video bandwidth than the sam460.

iirc, pcie 4x lane minus the overhead is about 1000mb/s, agp 4x is about 1033 or 1066 mbs but I dont recall if the agp 4x numbers are with protocol overhead removed.

[Louis Dias]

According to Applied Micro the AMCC460 does max DDR2-400 (peak speed 3200 MB/s). Mac mini G4 uses 166MHz bus though so DDR-333. That evens up the situation a bit, but for some reason Mac mini G4 still is faster.


Until RadeonHD has 3D drivers the whole question of Quake 3 performance is academic anyway.

And just as a final remark the work in progress MorphOS 3D drivers already run Quake 3 faster than Mac OS X.

From what I read:

400 MHz clock DDR2 memory controller

If this refers to the i/o bus then it's DDR2-800.  The internal memory clock is 200MHz for DDR2-800...

There appears to be some confusion about what it actually supports via the wording.  System designers usually only reference the internal or bus clock and not the "labelling".

Basically, whomever ran the tests should drop in some DDR2-800 (as it won't hurt anyways) and rerun the tests.

Kudos on improved 3D drivers.

[Louis Dias]

in actuality, its a 4x pcie-lane, and once you take protocol overhead out of the 4x lane, it pushes the same amount as the macmini agp 4x slot. so any of the g4/g5 macs that have an agp 8x slot can push more video bandwidth than the sam460.

iirc, pcie 4x lane minus the overhead is about 1000mb/s, agp 4x is about 1033 or 1066 mbs but I dont recall if the agp 4x numbers are with protocol overhead removed.

PCI-E is a serial connection. With data transfer going bi-directional. 16X up and down...while AGP is 8X only one way at a time.

[Piru]

There appears to be some confusion about what it actually supports via the wording.  System designers usually only reference the internal or bus clock and not the "labelling".

Applied Micro says "up to 3.2 GBps peak data rate". This translates to DDR2-400 (PC2-3200, 100MHz memory bus).

[Louis Dias]

Applied Micro says "up to 3.2 GBps peak data rate". This translates to DDR2-400 (PC2-3200, 100MHz memory bus).

Interesting, that site lists 1.0GHz max.
I wonder if ACUBE downclocked the bus but increased the cpu multiplier to achieve 1.16 GHz...  That would explain the poorer memory performance...

[runequester]

The MorphOS key file is 111 € (includes VAT).

ah, the wiki is wrong then, thank you for the correction.
It works out to 150 US dollars, plus whatever the cost of an old mac turns out be (lets figure 50 bucks for the G4 types). More than I am really comfortable with for something that doesn't have nostalgic value for me, particularly compared to the cost of a linux system on comparable kit.

If you guys support the G4 powerbooks within the next half year or so, once my wife retires hers for a new laptop in the summer, I promise I'll give it a shot. Don't want to mess with it at the moment, since she gets pretty particular about her computer. :madashell:

Also you can test MorphOS for free for as long as you like, 30 minutes at a time. After each 30 minute session the system slows down and you can reboot for another 30 minute testing period. There are no other limitations.

Nobody told me the trial had windows emulation :roflmao:

[antikk]

@piru

You're the ONE & ONLY reason i'll never get a mos license.

[antikk]

@piru

You're the ONE & ONLY reason i'll never get a mos license.

[zylesea]

If you guys support the G4 powerbooks within the next half year or so, once my wife retires hers for a new laptop in the summer, I promise I'll give it a shot.

MorphOS will probably support only the 1.67 GHz and the later 1.5 GHz. The earlier models don't use usb for kbd/tp. Hence, if your wife's pb doesn't happen to be a 1.67 GHz or 1.5 GHz (usb) model, it will not fit for MorphOS.

[runequester]

MorphOS will probably support only the 1.67 GHz and the later 1.5 GHz. The earlier models don't use usb for kbd/tp. Hence, if your wife's pb doesn't happen to be a 1.67 GHz or 1.5 GHz (usb) model, it will not fit for MorphOS.

it was one of the last G4 laptops they made but I dunno. I'd have to check.