General Knoppix support for those who've read the FAQ at the Wiki
Dell Poweredge R630 2x Xeon E5-2680 v4 2.4ghz 28-Cores / 128gb / H330 / 2x 1TB
$279.99
DELL PowerEdge R630 8SFF Server 2x E5-2690v4 2.6GHz =28 Cores 128GB H730 4xRJ45
$428.00
1U Supermicro Server 10 Bay 2x Intel Xeon 3.3Ghz 8C 128GB RAM 480GB SSD 2x 10GBE
$273.00
Colfax CX75432 4U Server 2x Xeon E5-2660 v3 NO RAM NO HDD NO GPU
$556.00
Dell PowerEdge R420 Dual Intel Xeon E5-2440 v2 @1.90GHz 32GB RAM No HDD H710
$74.50
Dell PowerEdge R620 Server 2x E5-2660 v2 2.2GHz 20 Cores 256GB RAM 1x 480GB SSD
$139.99
Dell Poweredge R210 II Server Xeon E3-1220 v2 3.1ghz Quad Core / NoRam / 1x Tray
$69.99
Dell PowerEdge R620 Server - 256GB RAM, 2x8cCPU, 120Gb SSD/3x900Gb SAS, Proxmox
$320.00
Dell Poweredge R730xd 3.5 2x E5-2690 v3 2.6ghz 64gb H730 14x Trays 2x 1100w
$489.99
Dell R730xd 26 Port SFF 2x E5-2697v4 36-Cores H730 128GB Server 2x SFP 10G ENT
$490.00