General Knoppix support for those who've read the FAQ at the Wiki
H261-Z61 2U 24SFF AMD Server 8x EPYC 7551 256-Cores 256GB RAM 8x25G NIC 2x2200W
$2812.18
Dell Poweredge R640 Server | 2x Xeon Gold 6132 | 128GB | H730P | 8x HDD Trays
$1849.00
HP ProLiant DL360 G9 Server | 2 x E5-2660V3 2.6Ghz | 64GB | 2 x 900GB SAS HDD
$339.00
CSE-118 Supermicro 1U 3x GPU Server 2.6Ghz 20-C 128GB CX353A 2x1600W PSU Rails
$454.03
Dell PowerEdge R620 Server 2x E5-2660 v1 2.2GHz 16 Cores 256GB RAM 2x 300GB HDD
$89.99
Dell R630 Server 2x E5-2620 V4 2.1GHz =16 Cores 128GB DDR4 1x 960GB 2x 1G 2x 10G
$210.00
Dell PowerEdge R730XD 28 Core Server 2X Xeon E5-2680 V4 H730 128GB RAM No HDD
$389.99
DELL PowerEdge R730 Server 2x E5-2680v4 2.4GHz =28 Cores 32GB H730 4xRJ45
$284.00
HP ProLiant ML350 Gen 9 Server 64GB RAM 2.4GHz Xeon 12-Core E5-2667 v3
$399.99
HP ProLiant DL380 Gen9 8SFF Server - E5-2698 v3 - 32Cores - 128GB Ram - 1TB HDD
$299.00