We've noted on a couple of occasions in this article that one of the X8 or X4 PCI Express slots on this new Asus motherboard could be utilized for something a bit more useful, in our opinion, than just a gaggle of graphics cards. And here's what we think makes sense perhaps for some of you looking to explore new areas of opportunity for enhancing overall system performance, with a few extra PCI Express lanes at your disposal.
- Intel IOP332 I/O processor
- PCI-Express X8 interface
- 128MB on-board DDR333 SDRAM with ECC protection
- Write-through or write-back cache support
- Supports up to 4 SATA II drives
- Multi-adapter support for large storage requirements
- Intel RAID 6 Engine to support extreme performance RAID 6
- NVRAM for RAID event & transaction log
- Redundant flash image for adapter availability
- Battery Backup Module (BBM) ready (Option)
- Street price currently = $315 - $350
The Areca ARC-1210 is a full "hardware RAID" solution based on Intel's IOP332 Storage Processor. This processor comes with an integrated PCI-X to PCI Express bridge so it can be utilized in either PCI-X bus (64-bit, 66/133MHz) or serial PCI Express designs like the Areca ARC-1210 SATA RAID controller we are using in the benchmarks we'll show you next.
Hardware RAID performance can be impressive under the proper conditions and in the right applications. We'll give you a taste of how to put that extra PCI Express slot to good use, as you'll see shortly.
First a few explanations on the graphs above. We ran the ARC-1210 RAID card in different slots on the motherboard, to look at performance over a X8 or X4 PCI Express connection. Scores labeled with "X4 SB" were taken with the card in the third slot which is enabled with a X4 PCIe link off the Southbridge in the 975X chipset. Scores labeled with "X8 Switch" were taken in the forth slot with a X8 PCI Express connection driven from the IDT PCI Express switch on this motherboard.
As you can see in our HDTach test results, the Areca RAID card in conjunction with the P5W64 WS outpaces the integrated Intel ICH7R software RAID controller on the motherboard by a significant margin, especially on burst reads and average write operations, which show over two times the available throughput with this PCI Express-based RAID controller, whether in an X8 or an X4 slot. Even on average read requests, the Areca card is nearly 15% faster.
Another observation is that there isn't a large performance degradation with an X4 PCIe connection versus X8 performance but the variations are larger for a RAID 5 configuration, where parity calculations on a third drive are required and add to the processing workload and bandwidth utilization. Another final observation would be that if you're considering running RAID 5 on a software-base ICH7R controller, you might want to seriously re-consider. RAID 5 performance with Intel's ICH7R is just that bad in comparison.