wonderlandlook just check if it lags on another computer. (use a game cause you need to upload when testing)
if it doesn't then fresh windows install, if that doesn't fix it get a new network card.
if it lags on all computers then unplug your router and use wired to modem.
(optional step, if you enjoy wasting your time) if it still lags call your ISP and they will check your signal strength and replace your modem. they will also lie about 'upgrading their network', do not under any circumstance believe them.
if it still lags get a new ISP.
the end.
The severity of the spikes fluctuate throughout the day which is kind of leading me to believe it's a network issue. I just blanked this HDD and my network card checks out. I've already tested with two different routers/modems. Talked to my isp and everything else along the network and still haven't gotten any response. Live in the middle of buttfuck nowhere so really there's only one ISP that services me
so basically i'm fucked