Power constraints for PCIe connections
Power constraints for PCIe connections
Hello! I own an Acer Aspire TC-380 pre-built, equipped with a Ryzen 5 2400G and integrated graphics. For light gaming, I chose the Biostar RX550 4GB, which fits my requirements. I upgraded the power supply to a Corsair CV550 and finally connected the GPU. Now, the RX550 operates without a traditional PSU connector—it only uses PCIe power. However, I noticed it only draws up to 25W, whereas PCIe standards suggest up to 75W should be possible. I’ve been searching for days, and often find similar advice copied from Wikipedia in posts like mine. There’s no clear guidance on configuring the card as a "high power device." I thought about enabling the PCIe Power Management/Saving feature in advanced power settings, but it didn’t help. I also considered using a riser, but those usually only connect via PCIe x1 and could create a bottleneck. The only riser I found uses a Molex connector from Moddiy, which is a bit unconventional. Anyone have any suggestions or solutions?
The RX 550 uses up to 45 watts of power... there aren't enough GPUs to draw more than that. If your card is restricted by the slot, use a PCI-E extension cable with its own power source, allowing it to run from a Molex or PCI-E 6 pin instead. For instance: https://www.amazon.com/Extension-SinLoon...07BNF4D9Q/
Where exactly do you find the manuals? If it was x1 riser, they wouldn’t have added that broad ribbon strip. It’s an x16 riser cable in my Amazon link, and the notes mention you can fit x1, x4, x8 or x16 cards into the slot or the riser cable—because that’s the way PCIe is built. The RX550, RX560 (and RX 460) support maximum PCIe 3.0 x8, with an x16 port that’s mostly empty since people keep swapping video cards because they don’t fit the x16 slot, or avoid buying them since their systems lack an x8 slot. The section before the notch holds power and reset/standby signals, while the part after is modular, offering up to 16 PCIe lanes with about 6-8 contacts per lane. You should notice this on the card itself due to longer ground traces separating the groups.
The details provided are inaccurate. If you're concerned, look for another extension that provides the additional power cable. Example links: https://www.ebay.com/itm/222928082316, https://www.ebay.com/itm/403405955065, https://www.ebay.com/itm/154779599932, https://www.ebay.com/itm/373812716861
I ordered one, it should be delivered tomorrow. I’ll keep updating here. Appreciate it.
I installed it, but everything remains unchanged—there’s a stuttering issue and it only reaches 25W maximum as measured. It’s confusing what to do next.