So I got my 3090 FTW3 Ultra on January 7th. Shipped from Newegg.
Keep in mind I was well prepared for this card. I have a Corsair HXi1200W PSU that I purchased in 2016. Never been pushed hard, as the fan has never even come on. i9-10900K @ 5.0ghz manual overclock @ 1.25v. Cooled by a bequiet Dark Rock 4. 32gb of DDR4 @ 3200mhz all on a Asus Maximus XII Hero motherboard z490.
So I did what most people do: overclock it. Set the power limit to 107% (not the full 110) and started to apply steady overclocks. Once I got to +100core/+400memory I found that I was stable there in all my games.
I had bought Cyberpunk 2077 when it released and at that time I was playing it on my 2080 super just fine prior.
Everything went well with my 3090 for about 3 days. I have my entire system plugged into a UPS so I can clearly see system wattage use. I noticed some very interesting variations and spikes in wattage. With my GPU overclocked entire system wattage would fluctuate from 590 to 710w at one point! My 3090 started to crash. I'm not talking about my system turning off or anything or even a driver crash. I was using MSI afterburner and my RTX was only getting up to 71 degrees...so it wasn't temperature. My CPU was in the upper 60s so it wasn't that either. I would play Cyberpunk and my system would just literally black screen. No bsod at first. With the black screen my system was still running fine, just no output, no mouse output, nothing. Because of this, I ruled out my PSU being the culprit because if it was my system would have simply shut off. The next few days I started to get BSODs that were not power related so that further strengthened my idea that it wasn't my PSU going out or not able to handle it. The BSODs were never Nvidia driver related though. I ran memtest just to be sure and nothing.
While researching I stumbled upon a video from JayZTwoCents talking about the 'MTCC and POSCAPs' issue with the RTX 3090 and 3080 AIB boards. Basically, if your card has just the POSCAPs it will have issues with overclocks approaching or over the 2.0ghz range. This was fascinating to me. So I examined my FTW3 to see and I confirmed that my GPU has the POSCAPs instead of the MTCC. Infact....my FTW3 has ALL POSCAPs on the back. After researching this....I fired up Cyberpunk again and using Afterburner kept my overclock which was putting my RTX OVER 2.0ghz. Sure enough.....my FTW3 was crashing when my GPU boosted to over 2.0ghz in Cyberpunk. I would get a freeze and a black screen almost immediately after that. I was able to replicate this 5 times in a row. What did I do? I lowered the overclock to factory settings and set the power level to default. NO crashes, No bsods, nothing. Overclock it to over 2.0ghz...crashes again with the computer still running but no output.
ONLY WITH THE POSCAPS:
POSCAPS WITH THE MTCC:
My conclusion: JayZTwoCents was right. If you ONLY have the POSCAPs on your FTW3 and overclock it heavily chances are high it will not be able to do it.
Just my experience so far. At normal 'OUT OF THE BOX' clocks my RTX 3090 FTW3 ULTRA is fine. These are just my observations.
post edited by Ascalaphus - 2021/01/15 08:54:31