I don't know how old are my PC's but i know they are all old and run great at least for my needs, here goes all my machines.
#1 Main Desktop and my Media Center; OPS WIN 10, 64 Bit
Lenovo ThinkCenter 81; chip-set 65, Intel (core)tm) I5 2400 CPU 3.10GHZ,
Mem 3.8GB,Socket 1155, Video card ATI 6450, HDD Sata 500.
#2. Main Desktop and My Media Center; OPS Ubuntu 14.04,64bit
Lenovo ThinkCenter71; Chip-set 61, Intel (core)tm) I5 2400 CPU 3.10GHZ,
Mem 3.8GB,Socket 1155, Video card ATI 6450, HDD Sata 500.
#3. HP DV-6 1259DX;64 Bit Intel Centrino duo core CPU 2.00 GHZ P7350
6GB Mem,Video Card Intel 4500HD.OPS Win 10,64bit
#4.Media Center With RF Analog Converter with RFCoaxial cable for all tvs.
Sony Vaio VGN A195EP; 32bit Intel Centrino Pentium M 1.5GHZ CPU
1GHZ Mem,ATI Radion Video card,60GB HDD,OPS Pro WinXP SP3.
#5. HP DV-5 1254US; 64Bit Intel centrino duo CPU 2.00 GHZ P7350,
Intel Video Card 4500HD,OPS Win 10,64 bit.
#6.Emachines EL1330 Amd Athlon 2850E 1.80 GHZ,4GB Mem,Ops Win 10 64bit
#7. Emachines T3958;32Bit Intel Pemtium 4 CPU 3.06GHZ,socket 478,
Mem 2GB,OPS Linux Xubuntu 14.04 LTS.
#8. Old Mac G5 PPC 2.00 GHZ 970 1 GB Mem,
OPS; Linux Debian Wheezy 7.1 PPC