OptimumOnline → constantly disconnecting, DHCP errors

I am getting constantly disconnected, it happens more often while I am playing an online game. It will happen randomly anywhere between 5-20 minutes, then it usually takes about 3 minutes to reconnect (the power and receive lights are lit, but the send light blinks when this happens).

when I look in the Event Viewer, I see many errors related to DHCP with time stamps at the times I get disconnected.

The IP address lease # for the Network Card with network address # has been denied by the DHCP server # (The DHCP Server sent a DHCPNACK message).

my internet has always been very stable with no disconnecting issues, but these connection issues started happening after some cable guy came and rewired the lines and disconnected the line leading to my room (leaving me with no connection). it was then reconnected, but since then, I have a very unstable internet connection now and its very aggravating because it disrupts my gaming. I have no idea if its something with the lines in my house now or what. my modem is 10+ years old and I am replacing it soon, but I am not sure if that will fix it (it was working fine all these years after all, until the issues with the rewiring).

its becoming constantly worse and its random. one day I will only disconnect once or twice, yesterday I didn't disconnect at all and today I disconnected about 20 times.

I do not have a router, I am connected directly to the modem. I unplugged everything from the modem to reset it, I fiddled with ipconfig commands, nothing works.

Since your modem is 10+ years old and the Cable guy did not replace it, I suspect you do not have Cablevision/Optimum Online. If you do not have CV/OOL this probably is not the correct place to get answers. Who is your provider?

I don't know that the DHCP is the source of disconnects, because the send light flashing is indicating that your modem has not locked on the upstream signal. How do the signal levels look on the modem? What IP is listed in the output of the DHCPNACK message - a public IP assigned to your computer or a private 10.X IP? If it's private, then that is cable-modem IP that is being NACKed, and you may have a modem that has its MAC cloned by another device. It's probably worth a swap, especially if this is a Cablevision modem where they will exchange it at no charge. If you don't have CV service, this would probably still apply as the boot-up process is the same, just to a different server & node.

If the IP in the DHCPNACK messages is a public IP, connect a different PC to the modem (and then reboot the modem). If it keeps giving you messages, you at least can rule out the NIC on your PC. If not, then possibly a NIC upgrade is required to cease issues.

I do have cablevision/optimum (it is the only cable company around here). the lines being replaced where the result of a cablebox not functioning correctly, nothing to do with my internet. the guy didn't even need to replace anything even (it ended up being a faulty box, or user error or somthing. I don't know since I don't watch TV or even have a box in my room). the guy didn't seem to care I used the cable for internet since he didn't bother to plug it in. we had to have someone else come back to see what was wrong and they plugged my line back into the splitter thing (or whatever it is, the hub?).

its a public IP. although, today, I only disconnected 4 times and there was no DCHP errors for those, this time. only one when I plugged the modem in at first. whats the signal levels? how do I check?

I will try the new modem when I can. I don't really have a way of testing the old modem on another PC. this 2nd PC I am now I dont stay on for more than an hour or so and I am not babysitting it to see if I get disconnected on here, since the disconnects are so random.