Hey All, Technical question here: I'm currently running a Crucial C300 64GB off of a SATA 2 port on my motherboard, and I need more SATA connectors so need an expansion card. (Currently I'm running without my DVD Drive!) My Motherboard is a GA-P31-DS3l, and I think it has PCIe x1 v1 slot. I'm wondering, because of the bandwidth restrictions of PCIe x1 v1 is it worth me getting a HighPoint Rocket card? I'm getting pretty awesome read speeds currently - should I just get a standard SATA II expansion card to free up some space, and save some cash? I figure that SATA II is 3Gbps, which is 375MB/s, and according to wikipedia PCIe x1 v1 is 250MB/s, so will it bottleneck SATA II (let alone III), or am I missing something? Cheers, Sam
Going on the discussions around the forum.. the Highpoint card will be limited to about 200MB/S in a v1 slot. So, not going to be worth it.
its slower in a PCI-E v1 than most onboard sata II controllers unless you've got a V2 slot, there is no point getting it.
Ummmm... Just to note, your speeds are hugely off for 3Gb/s SATA as you've ignored the 8b/10b encoding head... 3Gb/s becomes 2.4Gb/s (after the encoding overhead) -> 286.1 MB/s
If you just had the optical and a storage drive going through the expansion card and left your primary drives (os/games/apps/scratch) direct to the board i wouldn't have thought you would notice any real difference in actual use. Highly likely that i might be wrong though
What does the encoding overhead account for? Does this mean that it still needs 3Gb/s over the bus, but only 2.4Gb/s will be used for actual data. Or is the encoding an optimization? Yeah, that's what I reckoned I'd do, just run my DVD Drive off of the PCIe card. Oh...
What it basically means is that for every 8 bits that are transfered either way, an extra 2 bits are also transfered - so 20% of the total bandwidth is knocked off in encoding overhead... (for a very dull explanation as to the reason for this wiki has this) Afaik, the only common tech in the near future that's moving away from this to something more efficient will be pcie 3.0 which will use a 128b/130b encoding - reducing the overhead to ~1.6%... ...basically allowing what would be a 60% increase in bandwidth over 2.0 using 8b/10b to become a ~97% one. 2.0 -> 5GT/s @ 8b/10b -> 4GT/s. 3.0 -> 8GT/s if it used 8b/10b -> 6.4GT/s. 3.0 -> 8GT/s @ 128b/130b -> 7.88GT/s.
