Software PCI-e 4x(+) Raid?

[Mercutio]

Sorry for all the questions today!

Considering dual/quad core has plenty of spare juice to run the XOR raid 5 calculations is there any particular need to move to something like the rocketraid cards?
What advantage do they have over using a semi-hardware or just a random 4/8 port PCI-e SataII/Raid card? They dont seem to have the memory for caching (and aren't likely to benefit much from it either as not in a continual i/o environment where you'd usually see raid 5 used?) so apart from taking the load off the processor what other advantage is offered?

If the answer is "little" can anyone recommend a semi-hardware 4 or 8 port PCIe card? I find doing it purely in software in windows tends to be a bit of a chore (perhaps I havent done a pure software raid long enough to see) so semi-hardware would be prefered.
Selling this to myself on the premise that quad core = £120, rocketraid = £160+

Obviously if write operations are run MUCH faster on a hardware card ill be swayed back that way.

 

[Mercutio]

In that case would I be correct in thinking that for cost/performance raid 10 (strip+mirror or mirror+strip, whichever way around it does it thats different to raid 0+1) would generally be the best performance/price?

Considering 4 largish drives = ~£280 + 4 port Hardware raid 10 ~£55 = ~£335

Vs

Rocketraid ~£180 + 3 largish drives (for same capacity as the above) ~£210 = ~£390 with a probable performance loss over the raid 10.

Im basically after around 1TB of storage that suffer a drive loss without data loss problems so the raid 10 option seems slightly better in my case (Obviously not for yourself with much higher storage requirements).

 

[Mercutio]

Excellent, thanks.

As another option im considering (sorry to be going in so many random directions!) I see several external raid boxes. Some support Sata2 drives to Esata. If this was hooked up to a Sata2 connector on the mainboard would it give up to 300MB/sec or would it depend on the controller in the raid box (so in the case of a box that doesn't mention having a Esata2 connector id be capped at 150MB/sec)?

If it depends on the controller does anyone know a make/model for a suitable box? At the moment id want it for Raid1 if I was going this route so the extra throughput wouldn't be needed but as most of these enclosures support both it would a nice option to have further down the road for raid0.

If anyone knows of a 2xsata/sata2 to Esata2 controller that would likely help with my search.

 

[Mercutio]

Well aware your average (IDE/Sata) drive is lucky to push 90MB/sec so wont even touch sata port speeds. There are enclosures that do 2 drives to a raid controller to a single Esata (just google for esata raid enclosure, set it to UK only), my angle was at this point theres a chance a pair of drives in raid0 could exceed Sata port speeds.

I think my problem was not realising Esata was already specced to 300MB/sec.