Worked a bit trough the thread and now i know again, what finally prevented me from staying at the Snow Leo Developer: It was the lacking AGP-support.
So maybe, i give it a shot again in the Quad, which is PCIe.
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OWC Accelsior S
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So maybe, i give it a shot again in the Quad, which is PCIe.
Question answered: Yes, they do! Exactly as expected. Or should i say, exceeding expectations by far?
The card arrived today. Put a 500 Gig SAMSUNG 850 evo on it and swapped it into the Quad. Fired the machine up and minutes later was left a bit speechless. By numbers i had not seen on a Powermac before:
Thats what it came up with: Nearly hitting 400 MB/s with a single disk! Just what a Two-Lane-Card on a PCIe 1.0 can offer. And so far the Accelsior, at least for a G5, is the far better choice over the Sonnet Tempo SSD, which at the moment of writing costs four times it's price...while using the exact same Asmedia 1062 chip. Sure the Sonnet has Dual SATA Sockets. But, as it also only has a two-lane-interface, it is limited to the same speed as the Accelsior. Means: Even with two SSDs running in Raid 0 it will not be any faster than the numbers above! And to the G5 it is also nothing more than an "Unknown AHCI Standard Controller". Meaning, it will also not boot!
So for G5 users, looking for fast storage, the Accelsior S might be by far the best bang for the buck. Costing around 30 $/€ at the moment. For a card which, if not PPC-bootable, at least kicks the a... of even a 5,1's HD-trays! I'm very happy with my purchase...
...and allready edited the AHCI kext to show things right:
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Wanted to give it a try with the Quad today. But not too much luck again. The prebuild DMG restored to an empty SSD panicks when booting. And with the regular installation i get this...
...even with the OSInstall package replaced and permissions adjusted. 😟
I’ve not personally worked with the pre-built install image. The three times I’ve installed Build 10A96 on a system has come from the steps needed for installing onto a drive/partition from a working Leopard boot. It’s a little more work than a one-and-done image of a pre-built image, but it’s also more likely to work without the kinds of issues you’re seeing here.
Another note, which may or may not be relevant to your situation here: if I recall correctly, that pre-installed image was an installation onto a G4 setup (either a Power Mac G4 or PowerBook G4, though off-hand I don’t remember), not a G5. Running the installer from a Build 10A96 or 10A190 source, not the pre-installed image, would let the installer scripts assemble what needs to be installed onto your particular hardware. As others have been running both builds on Power Mac G5s (including quad G5s), we know it’s doable.
In short: first, boot from 10.5.8 (i.e., from an external FW drive or maybe a spinner drive on the OEM SATA bus which you don’t plan to use). Run through the steps needed to get the SL-PPC installer prepped for installation onto a destination location on your G5. Run the installer via that route. If you’re still having trouble, post onto the Snow Leopard for Unsupported PPC Machines (aka, the Clouded Leopard) thread, and I’ll do what I can there to assist. Hopefully, other folks who run SL-PPC on G5s (something I have yet to do personally) will be able to help walk you through the steps.
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Thanks for your kind reply!
Means, i don't have to run the installer from some external device (burned DVD, USB-stick etc.) but can just run it from my current Leo-Install to install Snow-Leo on the drive that is attached to the other SATA-port?
So mount the ISO, copy all the extensions to the said locations, replace the installer.mpkg, repaire permissions?
Potentially stupid question: Can i just initiate the install from the mounted (and patched) ISO file? Doesn't the installer have to reboot and for that be on some real device (i. e. DVD). Or will the first reboot allready be from the fresh installed disk?
Yes, sure, i'll have to come back to you. Thanks in advance!
Yeah, because AHCI PCIe SSDs are scarce and pricey compared to NVMe and SATA ones. A four-lane PCIe SSD will run circles around the Accelsior. And we’ve seen the Samsung SM951 works just fine with Leopard’s AHCI driver on PPC.
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So nothing easier than swapping this thing (without the adapter of course) in a Quad, where, if the card is really four lane, it should not be bottlenecked at all. But i still don't expect anything more than about 500 r/w. So not that much of "circels". 😝
Suggestion seems to be not that wrong! They get 1.100 here. But this is PCIe 2.0. So take half of it and you should be allmost there. Also these blades seem to be a bit hard to find nowadays. Google anyway just came up with a lot ofadapters. But, at least on the first pages, not one single SSD.
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The SM951 does use four lanes (datasheet). Nonetheless, it will still be bottlenecked by the Quad's PCIe 1.0 interface.
Why? Four lanes of PCIe 1.0 allow a theoretical maximum of ≈1000 MB/s. On a 2011 MacBook Pro, I get 735 MB/s sequential read from a Samsung 970 Evo via Thunderbolt 1 (which is four lanes of PCIe
These results are for the XP941. The SM951 is faster. Also, why do you expect four lanes of PCIe 1.0 to only get 500 MB/s? If two lanes get nearly 400 MB/s according to your own results, I'd expect four to sit somewhere between 700 and 800 MB/s.
Fortunately, Apple used the XP941 and SM951-AHCI in a couple of Macs. Their version of the XP941 is called SSUAX (careful: it uses only two lanes unless you go for the 1TB model). Their version of the SM951-AHCI is called SSUBX (all models use four lanes). These two are very easy to find on eBay etc., but they need a custom PCIe adapter as they have a different pinout than the Samsung versions. But these adapters are also easy to find and cheap (not my auction, but this is the adapter I have).
More info pleaseWinner: G5 7,3
What SSD and SAS controller is this?
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This looks like an Areca ARC-1160. Your results look like they're coming from the Areca's on-board DDR cache rather than the SSD itself, since the card is SATA II. "Stimmt's oder hab' ich Recht?"
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Kann sein"Stimmt's oder hab' ich Recht?"
But arround 550 MB/s are possible with two SSDs, but i have no free SSDs for a 3xSSD RAID at the Moment to bring the card to the maximum.
The big question is, then: Can we get closer to 133 MHz PCI-X’s (theoretical) limit of 1064 MB/s?Kann sein
The Problem is, all my RAID tests were with 3 different SSDs (vendor, size). So I don’t have realistic data.
I would say the real limit is 750 MB/s like PCIe 1.0 x4.
By the way: Aren't the XP941, the 970evo as well as the SM950 all NVMe, which the Powermac just does not support?
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Nice! And yes, i was very disappointed by the performance of this LSI SAS controller, which basically equals the G5's SATA I.
Does this Areca even boot?
The XP941 is AHCI (as mentioned here).
The SM951 is available in both AHCI and NVMe versions, so you need the correct one. I linked to the datasheet of the AHCI version in my earlier post and it explicitly says “Support [sic!] standard AHCI driver”. Proof: the French article I linked to elsewhere shows the SM951-AHCI being recognised in Leopard on a G4 as “Unknown AHCI Standard Controller”.
The SSUAX and SSUBX, i.e. Apple’s variants of the XP941 and SM951, are all AHCI. Proof: I’m booting Mavericks (which doesn’t have NVMe support at all) off my SSUAX. I’ve also ordered a 256GB SSUBX I’ll be testing with Snow Leopard (via Thunderbolt 1 on a 2011 MacBook Pro) and Leopard (via ExpressCard on a 2007 MacBook Pro).
The 970 Evo is, in fact, NVMe.
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I am a bit confused now. NVMe- and AHCI-versions seem to have the same connector. Do they use the same adaptors too? Meaning, can a NVMe-PCIe adaptor be used for an AHCI blade too? This would be nice, as i have two of them which i have no real use for anymore.
Yes, both use the same M.2 "NGFF" connector.
Which blades are these, just out of interest?
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Not SSDs, adaptors. And no notebook formfactor. The ones i used in the 5,1 before i got this RAID-card.
...and, if these blades like the SM951 work in Powermacs, a single one should easily saturate one of the four lane sockets. It would then, even not bootable, be one of the simplest and IMHO the far best fast storage solution. Cause it has the same or nearly same speed in sequential transfers of big data without all the downsides of a RAID in random small transfers and safety.
If it is not for tons of chunky video files, all those complicated and expensive RAID-solutions are mainly for benchmarks. In particular when talking of boot-drives.
Just checked the usual suspects...just to see that there are crazy amounts asked for the AHCI-variant. 130 Euros and up, even for used 256GB parts! That's what you easily get a 970evo plus 1TB for! 😵
This is just what I've been trying to say.
But since I don't have a PCIe G5 to test my SSUBX in, would you be willing to buy one and the custom PCIe adaptor to give it a try yourself? You can get a 256GB SSUBX and adaptor for less than 50 Euros (see next paragraph).
You can get a 256GB SSUBX, i.e. Apple's variant of the SM951-AHCI, for a fraction of that. I just bought one for 35 Euros (not my auction; I made an offer for 30 Euros and 35 Euros was the seller's response).
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