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I would like to know if anyone has an opinion. On the E version it offers either the Intel raid or using the on board Promise raid.

Is one better than than other. I should add that I currently have the P4c800 Dlx and had received the E version recently.

My current configuration

2 Maxtor 6Y120MO set up as raid on the SATA
2 Maxtor 6Y120PO set up as raid using the Promise.

My other specs
3.0 CPU
4 x 256 Kingston value ram

Thanks in advance for your comments
 

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You asked for opinion, so here's one. (Caveat: I don't use RAID myself.)

First, I am assuming you mean RAID-0 (your only choice with the ICH5R). Assuming that is what you meant, then...

Providing when you say "on the SATA" you mean on the ICH5R "SATA1/2" ports, IMO that will get the most RAID0 performance for your mobo. Each of the dual SATA controllers will operate independently, mastering their own transactions onto the HI (Hub Interface) bus which gets you to memory, a bus which on these mobos operates at 266MB/s (Megabytes per second).

Potential downsides of these ports are Intel's lack of RAID experience compared to Promise, and fewer varieties of RAID offered there than on the Promise. Also I think you might need to run with the "IAA" (Intel Application Accelerator), software that's not needed with the Promise; this might be an option, I don't know if it's a requirement.


In contrast, the Promise hangs off the PCI bus, which has to squeeze through a bridge to get to the HI. This is a 32-bit PCI bus so it's constrained to 133MB/s theoretical max (your mileage will be less), which happens to be half the HI's bandwidth. Also sharing this bus are all your Firewire ports, plus any add-on PCI cards you may attach. Now, your RAID may not achieve 133MB/s, but if each disk manages 45-50MB/s, you can approach it, and this will leave a lot less bandwidth for any other PCI devices.

Worse, your 6Y120P0 ATA/133 disks are sharing an IDE bus cable on that Promise. IMO this is the least efficient way to run RAID on this mobo, because as I understand RAID0, each disk will own half the data. In order to read or write your data, you need to access both disks. Yet whenever one disk is using the shared IDE bus, the other disk must wait. On-disk buffering helps things a little, but not for sequential accesses.

If, instead, you were comparing Promise "SATA RAID1/2" ports to the Promise IDE port, then I think the Promise SATA ports will be more efficient than its IDE port, due to the lack of bus cable sharing, and also more independence on the part of the controllers within the Promise. Still not as good an arrangement as using the ICH5R SATA ports, though, again because of the PCI bus.

I had one more point to add, but I forgot it.

Hope this helps,

-clintfan
 

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Thank you Clintfan,

I have been searching quite a bit for this and you were able to clear it up fo me in a couple of paragraphs. I have been a strong fan of raid for a long time now and had forgotten some details.

My current situation is that I'm using the Promise SATA raid, and getting up to 52mb (Sandra) but only 29mb on the Promise IDE whereby in the past I was getting to the 40's on the IDE.

You hit the situation right on the money, because my raid configuration in the past was each hard disk had it's own cable and not sharing one.

As I will be changing my Asus P4C800 DLX to the P4C800-E I will definetly explore the Intel raid option because of your explanation regarding the bandwidth. It makes perfect sense.

Thanks again

Randallizer

PS I agree with some other readers that Asus should be giving you a stipend.
 

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Glad it helped. Oh, and I just remembered that other thing I had forgotten. I was going to thank you for answering whether or not dual-IDE-drive RAID0 at least functions on the Promise "PRI RAID" IDE port. Now we know, yes it does, just not very well (as expected).

-clintfan
 
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