Slow download; ok upload

[Ekecko]

I just installed an AC1900 router and a AC400 modem.  My download speeds are slow but the uploads are fine on my desktop (Win 10).  My laptop is fine in both directions.  What is the problem?

[FURRYe38 · Accepted solution]

Hmmm brings to mind someone recently had a similar issue with a NG modem and could not get that modem to work well with the NG router. They ended up swapping the modem for a different Mfr modem....was just a month ago I believe in this forum. Don't remember the date. If you swapped the modem and your porblems appeared, I would think the modem maybe the issue. Might want to check out a Arris 6183 and see if the problems continue. 

[FURRYe38]

IF your Laptop is fine, then something on the WIndows 10 PC could be the problem. Besure to disable any PC security programs while doing downloads. Try rebooting the PC into Safe Mode with Networking and see if there is any differences. 

Does the modem have a built in router or is it a modem only? 

Swap LAN cables between the PC and the router. 

[Ekecko]

I agree, it seems like a problem with Win 10.  I switched out the LAN cord between the modem and router and noted an increase in speed from 1 MBps to over 5. (Laptop on same system is > 20) I can't figure out how to start Win 10 in safe mode but I have disconnected all PC security and firewalls with no effect.  I think there may be a problem with the modem.  No problem with the old (>15 yr Motorola) modem but when I switched out to the new NetGear, problems started.  Thanks for all your help; any ideas?

[FURRYe38]

What is the MFr and model of the ISP modem?

Motorola modems are good. Up till Arris bought there modem division a few years ago. Be aware that there is a major problem with the Arris SB 6190, however the Arris 6183 is good. It's Broadcom based where the 6190 is Intel Puma 6 based and has the problem with any modem with this chip set.

[Ekecko]

Netgear CM400 Modem and Netgear AC1900 Router.

[FURRYe38 · Accepted solution]

Hmmm brings to mind someone recently had a similar issue with a NG modem and could not get that modem to work well with the NG router. They ended up swapping the modem for a different Mfr modem....was just a month ago I believe in this forum. Don't remember the date. If you swapped the modem and your porblems appeared, I would think the modem maybe the issue. Might want to check out a Arris 6183 and see if the problems continue. 

[Ekecko]

This is crazy.  Since your suggestion I have tried 3 different LAN cables, each with significantly difering results.  I think I amgoing to go with the Arris and give it a try - can't explain any of this but I am making progress.  Thanks so much for the help.

[FURRYe38]

Let us know how it goes....