SCSI Help

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Right, I can get SCSI drives through work FOC, thought I could put a couple into RAID0 and have them as my OS drives.

Which card/cables would I need to get to make this work? The drives are Ultra320 80 pin. Not looking for something ridiculously expensive...

Got a PCI Adaptec AIC 3860Q here if that could be used; but I don't think it's got RAID on it? Any other little bits I'd need like power adaptors etc?

Basically just need a list of what's needed (my current spec in sig) with eveything included apart from the drives. BTW the one's from work are all 15k HP drives, most are 74GB but some are 150GB and I've spotted a few 300GB ones.

Finally, would I notice a difference? Apps, games and WinRAR stuff wise...
 
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The first thing you'll need are 80-68pin adapters. The drives you describe are hotswap ones with a SCA integrated power and data connector so that needs to be separated into a 68pin U320 SCSI port and a 4 pin molex power socket.

You'll then need a U320 cable which is going to set you back a bit - £50 for a 5 drop one isn't unrealistic. The 3860Q looks to be a U160 card, not a big deal since SCSI is backwards compatible but if it's a plain PCI card then it'll bottleneck the drives so you'll only benefit from low access times rather than fast transfers.
 
Thanks. I'll have a dig around, should be able to find some cables. Was thinking of a Dell Perc card, which one would I need that won't bottleneck? Is it a PCIe one or PCI-X?

Already seen the adaptors for sale for a reasonable price.
 
Right so the PCI-X is server only (mainly), new GFX cards go in PCIe, so what's the little one? Is that not PCI-X as well? Or am I completely confused... Seen a LSI MegaRAID 8308ELP, and it has the little connector?

Sorry for the questions, I'm learning it all here!
 
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PCIe slots come in various sizes depending on how many "lanes" they support, each lane being a 250MB/s serial link which can be parallelised (is that a word??) to provide more bandwidth. The 16x slots have 16 lanes and can take any cards, occasionally you'll get a 4x slot which can take 4x and 1x cards then most boards now have a couple or three 1x slots.

Graphics cards are mainly 16x, SCSI, SAS & SATA cards are 8x for high end stuff and 4x for midrange. 1x is used for low bandwidth devices - sound cards, cheap SATA cards, NICs etc.
 
It's probably the most cost effective way of doing SCSI RAID on PCIe. There are very few PCIe SCSI cards about - Adaptec do one and it doesn't support RAID, LSI do one but new it's £400. Or you could pick up the Dell which is the same card for half that.
 
Am I reading an article wrong or can the Dell Perc do SATA as well as RAID? Also, how would the Dell handle 3 X HP 150GB 15K drives in RAID5?

And finally for quick transfer I take it I'd be limited to the Dell Perc in PCIe form?
 
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The Perc/5i is a SAS card (Serially Attached SCSI), SAS cards can handle both SAS and SATA drives (they use the same connectors).

The Perc/4i is a U320 "parallel" SCSI card and hence is limited to old style SCSI drives.

Just be aware that you can't put SAS or SATA drives on a U320 card nor can you attach SAS drives to a SATA controller.

You will need the PCIe version of the Perc for best performance.
 
Thanks for all the help mate. Sounds quite daunting with all the cables, adaptors and cards. Is is worth it in the end? Not sure how much the drives normally go for but I just thought that with the drives being FOC it would be. I've got a choice, can get two 146GB, two 74GB or two 35GB, or even all if I really wanted.

Is there no cheaper solution for sub £100 for the controller card?

Thanks for all the help, really appreciated by the way.
 
Free SCSI drives are always tempting especially when you see that they retail for anything from £150 to £500 a pop however with everything there are downsides. A 10krpm 150Gb SCSI drive isn't going to give you much of a performance difference to a 150Gb Raptor, it's only when you go to 15krpm that the differences become clear. Then you have to remember that 15krpm drives are noisy little beasts too.

While SCSI is a nice thing to play with (and you'd be doing a lot of that to get it working) there isn't a convincing performance argument to use it over SATA now really. I'd take a look on eBay and see what equivalent drives are going for, you might have the opportunity for a nice little earner ;)
 
They are the 15k drives. As for noise, I'm used to four Raptors whirring away so I don't think SCSI drives would bother me. Plus I've got 4 120 mm fans, the WC is for overclocking not noise limitation. PC is used for watching films, gaming and browsing and 9/10 I've got something or other booming through the speakers!

I guess my main reason for wanting to do this is that it's something I've never done before and I enjoy messing around. SCSI is something that's always interested me, but whenever someone has suggested doing it I always used to hide behind my Raptors!

I think I'll keep an eye out for a Dell Perc card, I have plenty of friends who are network admins so one of them might be able to get hold of one on the cheap. I think I'll buy the Ultra 320 cable and adapters in preparation.

Is there anything you can think off that I might need to know; finally are they easy to get an OS onto them once everything is in the PC?
 
Installing to SCSI is just like installing to SATA - make sure the boot order is right and give the OS the right drivers then everything's plain sailing. The big trick is getting the SCSI stuff working, with up to 15 drives per cable you need to make sure all the IDs are set right and that the cable is terminated correctly at each end.
 
Well I've decided I'm going to do this. I was originally going to get two more 640AAKS drives and run four in RAID 5, but for the same price I can get a working Perc card from ebay. I think the SCSI option will be better, especially the storage difference won't be too large.

I've found some Ultra 320 cables on the bay for about £15, the adapters aren't too expensive and the drives, as before, are FOC. Just got to keep my eye out for a Dell Perc PCIe card now. Just a quick reiteration for myself, can I use both the little PCIe card types and the long GFX type ones?
 
Just a quick reiteration for myself, can I use both the little PCIe card types and the long GFX type ones?
Not quite sure what exactly you're asking. Do you want to know which slots can be used simultaneously or what slot you need free for the Perc card?
 
Right I have a choice of the following two:

Dell PERC5e PERC 5e SAS PCI-E 256MB Controller w/BBU

DELL PERC 5i SAS RAID 256MB SCSI PCI EXPRESS CARD + KIT

Which is the better choice and will they both work? lol

If the card can run SCSI drives and my SATA drives that'll be a bonus.

Both about the £100 mark.
 
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