This is almost certainly the issue.
Cat 5 cable gigabit speed.
It was once believed that achieving gigabit speeds with ethernet would require the use of fiber optic cables or other special network cable technology.
The category 6 augmented cable standard or cat 6a was created to further improve the performance of cat 6 ethernet cables using cat 6a enables 10 gigabit ethernet data rates over a single cable run up to 328 feet.
For most purposes gigabit ethernet works well using a regular ethernet cable specifically the cat5e and cat6 cabling standards.
The old fashioned cat 5 cable is no longer a recognized standard but it technically supports gigabit speeds just not well.
If you have gigabit internet 1gbps an old ethernet cable will hold you back.
Cat 5 is also used to carry other signals such as telephony and video.
Cat 6 supports 10 gigabit ethernet only up to 164 feet of cable length.
More recently the introduction of cat 7a cable increases the speed to 1ghz and throughput to 40gbps but tops out at 165 feet.
Cat 5e cable is enhanced to reduce interference so that it can reliably.
Fortunately those are only necessary for long distances.
If you have a slower connection perhaps 10 or 20 megabits per second you re good with anything cat 5 or newer.
In other words only some of those old cat 5 cables are good enough to be cat 5e cables.
Cat7 ethernet cable 20 ft rj45 connector cat 7 double shielded stp 10 gigabit 600mhz premium high speed 6m network wire patch lan cord 20 feet 4 8 out of 5 stars 199 13 89 13.
Category 5 cable cat 5 is a twisted pair cable for computer networks since 2001 the variant commonly in use is the category 5e specification cat 5e the cable standard provides performance of up to 100 mhz and is suitable for most varieties of ethernet over twisted pair up to 1000base t gigabit ethernet.
Cat 6 and cat 6a cables are more interesting.
The new 2ghz speed limit finally category 8 is the new.