Issues relating to HDD Installs. Once you have installed Knoppix, it basicly becomes debian, so you should check out www.debian.org for information.
Dell PowerEdge R710 2.5" 2U Server 2x X5670 2.93GHZ 12-Core 128gb 2x 1TB SAS
$114.99
Dell PowerEdge R620 Server 2x E5-2660 v2 2.2GHz 20 Cores 256GB RAM 1x 480GB SSD
$139.99
DELL R630 SERVER 8 x 2.5'' 2X E5-2680V4 32GB RAM IDRAC ENT & NDC 2X 495W PSU
$169.95
Dell PowerEdge R730XD 28 Core Server 2X Xeon E5-2680 V4 H730 128GB RAM No HDD
$389.99
Dell PowerEdge R720xd 26HDD 300gb 2.5-inch E5-2697 X 2CPU 384RAM 7.2 Tb HDD 
$180.00
Dell PowerEdge R620 Server - 256GB RAM, 2x8cCPU, 120Gb SSD/3x900Gb SAS, Proxmox
$320.00
Dell PowerEdge R640 Server 2x Gold 5220 = 36 Cores, 384GB RAM, 800GB SSDs, H730p
$1200.00
Dell PowerEdge R630 Server 2x E5-2640v3 2.60Ghz 16-Core 64GB H330
$182.65
Dell Poweredge R630 Server 2x E5-2620 V4 =16 Cores | S130 | 32GB RAM | 2x trays
$153.99
DELL PowerEdge R630 8SFF Server 2x E5-2650v4 2.2GHz =24 Cores 32GB H730 4xRJ45
$240.00