2 hours ago, Syn. said:
the TX850 PSU is already highly regarded, why the hell would you need to upgrade it? and it's plenty of capacity for the RTX 3090, it's a waste of money to buy a 1200W PSU
the Bronze rating does not matter much for the quality of the PSU and it isn't future proof to do senseless purchases
I think you're confusing the TX850 with the TX850M. The 80+ Bronze rated TX850 is the TX V2 from 2010. 10 years old... Don't use a 10 year old power supply with a $1500 graphics card!
3 minutes ago, Ashino said:
I noticed that the Corsair HX1200w has a mutli and single +12v switch in the back. I'm not really sure what that does or if it matters at all. Could you explain to me what it does and whether I should use single or multi rail?
It switches the 12V rail between single rail and multi rail mode. Multi rail mode will enable the OCP on the virtual 12V rails to prevent you from drawing too much current through a single cable. Not important for normal operation, though in a small percentage of certain failures if other protections don't kick in it might help to shut down the PSU to prevent further damage. For the Corsair HX I believe it's 40A limit for the 12V rails when in multi rail mode. It should come set to multi-rail out of the box and you can just leave it in multi rail mode. The only reason to switch to single rail would be if you have problems with the 3090 drawing too much power and causing it to trip that OCP when in multi rail mode, but I doubt it will be an issue unless you're doing power mods to the card. Your current TX850 is single rail, btw.
2 hours ago, Ashino said:
I would like to stay under $400 if that's even possible.
I guess that rules out the AX1600i then. Go with the HX1200 Platinum, but make sure you find one that is actually close to MSRP and not stupid inflated prices due to the pandemic. It should be around $230-$250.