Which way would you do it?

gtghm

I am making some changes to my system.

I have a WD JB 250gb drive that I am going to use as a C drive and back up for my 200gb Raid 0 array.

The raid card is the 3 ware 7500 (4) port raid card.

The choices are either I install it on one of the 2 remaining free ports and boot off the 3ware card and basically run off the 3ware card for everything.

Or

I install the drive on an IDE.

I currently have an 80gb drive that I am useing for my C drive installed in an IDE.

You should know, if you don't, that the board I am running is a Supermicro dual Xeon board. The 3ware card is in a 66/64 slot.

I assume that If I install it on the 3ware card running in a 66/64 slot I should have an advantage because the 66/64 bus is not on the same buss as the 33mhz/PCI bus thus I should see a bit of a performace boost... yes?

Thanks,
"g"

Thrax

A single hard drive will see no performance boost on a 66/64 slot, as the drive itself scarcely begins to touch the performance of a 33/32 slot.

So it wouldn't really matter where the drive goes. It's about what would be convenient for you.

Straight_Man

I would expect a slight performance boost out of the 66\64 card in this case. That drive can burst chunks of buffer size (RAM on HD controller card embedded on mech) and WILL if pushed. So, if you have large files a lot then it woudl make sense to do this so long as your O\S will BOOT off the PCI 3WARE card in that config.

For normal use with a mix of file sizes, as Thrax said, definitely does not matter and safest is to have the boot drive on an IDE unless the main system BIOS supports booting from the 3WARE card-- most do not boot off of PCI adapters, which is why the boot thing is important, and why embedded is better than PCI if you want to run your WHOLE array on otehr than IDE.

You have a card capable of mirroring and getting the mirror well done without needing the boot drive on the 3WARE if you use software and soft mirror (I count XP Volume Management as soft mirroring), plus unless you have other PCI 66\64 slots filled the 66\64 will have less bus load on itself for data flow than a fixed single speed PCI bus for all slots would have-- this is the other reason for the drive and card doing best on 66\64 connect.

The traces for the 66\64 on a mixed system are deidcated to 66\64 from the controller, so in essense you have a mini-high-speed PCI bus except as for shared system resources like IRQ and port assignment, and buffers. It is quite possible that the partial isolation of bus in this matter will also lead to the card drivers grabbing a bit less RAM also, as RAM buffering can be dynamic and if the card drivers are designed this way they will tune to throughput and buffer less in RAM.

I would say a 5-20% net performance gain overall in system with this card as 66\64 if the drivers are written to dynamic buffer(newer ones should be that way). You might get to reload the 3WARE drivers if you do not mind that, to get max performance.

The one thing, if you have an existing array, moving and\or reloading will break your array so write down exactly what you have first if you want to have any reasonable easy chance of using the drive contents after this change and back up everything first before even moving card as lots may change when you do.

John. (little longer than would like, but bus inter-relations are complex and data loss chance is high doing this.)

Spinner

Thrax said
A single hard drive will see no performance boost on a 66/64 slot, as the drive itself scarcely begins to touch the performance of a 33/32 slot.

So it wouldn't really matter where the drive goes. It's about what would be convenient for you.

I tend to agree, but there may be a slight increase, as Ageek suggested, but I personally feel it will be so marginal that it doesn't really bare thinking about.

I say the same as Thrax, go with whatever is most convenient.

Cheers

Tex

Thrax said
A single hard drive will see no performance boost on a 66/64 slot, as the drive itself scarcely begins to touch the performance of a 33/32 slot.

So it wouldn't really matter where the drive goes. It's about what would be convenient for you.

Depends on the controller my friend. You get more then just total bandwidth. With 64/66mhx its actually moving data faster sooner. You ramp up faster IF THE CONTROLLER is made to handle it. Your peak score as far as transfer rate doesn not change but it moves data faster through the whole range often.

Great example. My HPT 4ch 1540 was advertised as 66mhz capable and the box says it is but now HPT changed their mind and say its not but.... In the MSI-k7d with it stripped down and hardly any cards in to jack with each other...

On atto on the first line for instance in a 64/66 slot I hit the same on writes bascialy with a two drive raid-0 but the reads are almost doubled. From 7000 to 12000 on the first line alone. with it just being slipped out of the 32/33 to a 64/66. No your top scores on atto won't change as total transfer rate didnt change much but stuff like Sandra show a jump. And teh low end on ATTO will change often also. 64/66mhz has more use in real life then your seeing so far!

My high dolalr scsi controllers iwth teh risc cpu's and cache will run in a 32/33 slot too but not at nearly the speed even for a single drive. Its strictly controller dependent

Tex

Mt_Goat

If you guys look up the specs on the controller in question, it is 64/33 not 64/66 because he did mention it was the 7500.

Tex

It still benefits from the 64/66mhz slot. Just like a 32bit card/66mhz capable card like the cheap promise ide controllers do.

Tex