It functions on any PC except yours
It functions on any PC except yours
The title provides a brief overview: it explains the situation with a second-hand Corsair CX550-RGB graphics card, the hardware configuration, and the troubleshooting steps taken. It also mentions previous successful setups and the user's efforts to identify the problem.
I understand but it doesn't clarify the unusual actions either. Also, the cards don't consume the complete 270 watts each when starting or idling—it shut down right away when power was pressed.
I generally concur. A second opinion would focus on the splitter quality. However, if you're noticing unusual behavior and it's happening, I'd just stop here. You seem to have other priorities, and it wouldn't be worth the effort or impact. (By the way, I'm puzzled about how they achieve 270W with a mb PCIe 75W + 2 × 6-pin 75W = 225W.) Edited May 19, 2024 by leclod
In short, you're putting too much load on the power supply unit. A 550W unit seems way too small for your needs. Ideally, a PSU should have about 20% extra capacity to handle spikes and future upgrades. This kind of unit is better suited for smaller builds or integrated graphics setups. I’d suggest choosing a bigger one—around 800W in a fully modular form would be a good choice and cover all your requirements.
R9 270x consumes just 180W max power. https://www.techpowerup.com/review/amd-r9-270x/24.html https://www.techpowerup.com/gpu-specs/ra...270x.c2466 Running two would add about 360W, plus the rest of the system brings it to roughly 450-500W. Performance drops under heavy load, not during startup. It should work with the CX550F. It might be better to avoid PCIe splitters and opt for the TX750 instead. Crossfire setups aren't recommended anymore; a single R9 270x in crossfire is likely to underperform compared to today's mid-range options.
Using 'the psu' means the CX550 v model. I ran some tests this morning and noticed the splitters functioned as expected on another PC with the same PSU. When I started the PC using the TX750, it triggered error messages like "Post failure" and "Bios configuration error," even though the BIOS works perfectly with other PSUs. Connecting the PSU didn't provide power to my motherboard at all—super strange.
I suspect the AC240 wall power splitter might be the issue, as it was connected to multiple outlets and failed after internal damage. The problem seemed more pronounced in the room where the outlet was dead, whereas testing with the TX750 in another space didn’t trigger the same failure. I think the motherboard could have taken a hit because the OC appears less stable now.