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Alan McKinnon wrote: |
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> My notebook works like that too. |
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> |
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> Hard disk works fine when everything is set to AHCI, but then the system won't |
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> boot from CD. So I enabled the IDE driver and the IDE driver for CD-ROMs. |
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> |
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> My take on this is that Dell had a vast stock of cheap-skate CD-ROM hardware |
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> and used them up. The engineering logic would have been "it doesn't matter |
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> that we use the slow interface for that device, it's still faster than we can |
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> get the data off the media." |
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> |
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> |
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|
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And I thought there was something weird with me on this one. o_O I did |
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switch it back to AHCI after I got done booting the CD thingy. I really |
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can't tell any difference in speed between the two and neither could |
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hdparm -tT either. |
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|
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root@fireball / # hdparm -Tt /dev/sda |
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|
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/dev/sda: |
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Timing cached reads: 6408 MB in 2.00 seconds = 3205.06 MB/sec |
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Timing buffered disk reads: 328 MB in 3.00 seconds = 109.22 MB/sec |
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root@fireball / # |
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|
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I get about the same either way. Could that mean that when the kernel |
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boots that it switched over to AHCI regardless of the BIOS setting? |
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This is a little info too: |
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|
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root@fireball / # dmesg | grep -i ahci |
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[ 0.827837] ahci 0000:00:11.0: version 3.0 |
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[ 0.827855] ahci 0000:00:11.0: PCI INT A -> GSI 22 (level, low) -> IRQ 22 |
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[ 0.828285] ahci 0000:00:11.0: AHCI 0001.0100 32 slots 6 ports 3 Gbps |
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0x3f impl SATA mode |
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[ 0.828840] ahci 0000:00:11.0: flags: 64bit ncq sntf ilck pm led clo |
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pmp pio slum part ccc |
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[ 0.830342] scsi0 : ahci |
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[ 0.830734] scsi1 : ahci |
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[ 0.831103] scsi2 : ahci |
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[ 0.831474] scsi3 : ahci |
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[ 0.831843] scsi4 : ahci |
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[ 0.832204] scsi5 : ahci |
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root@fireball / # |
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|
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Someone may can talk be into rebooting and switching AHCI off and |
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testing again. Big may there. ;-) |
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|
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Dale |
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|
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:-) :-) |
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|
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P. S. Seriously off topic. I used hugin the other day to stitch |
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together about a dozen pics from a 10Mpxl camera. It was awesome to |
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watch all four cores crunch on that thing. It was fast too. Going from |
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a single 2.5Ghz CPU to a four core 3.2Ghz CPU is a huge difference. |
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