This situation is quite unusual.
This situation is quite unusual.
Maybe it's because his son's computer uses an AMD A6 APU, but during Fortnite he struggles more with a Geforce 560 Ti compared to when I used my Radeon HD 6750. Neither of these graphics cards is the best today, but we're stuck with what we have right now. By all means, the GeForce should perform better. The power supply isn't a problem—I replaced it with a 550W ATX unit I found.
(I'm upgrading his system tonight; I'll get a new or used one with an i5 3450. It's running on an H67 motherboard, but I got it for 25 dollars. No HDD and 16 GB of RAM, so it should be better than the old HP system he's using now.) I also plan to install an SSD and possibly a new graphics card for his birthday in July.
TLDR: Why is a Radeon HD 6750 outperforming a GeForce 560 Ti in Fortnite?
Which APU is being used? I believe the 6750 fits with several APUs' iGPU in "Dual Graphics" mode, a hybrid crossfire setup. It might not offer enough improvement to change the game, but it could enhance performance more than expected when paired with the HD 6750. Now, you're pointing out that comparisons are being made mainly about lag instead of graphics speed. Without a clear performance measure, it's tough to give a proper explanation. There might be software reasons at play—perhaps one GPU driver struggles more with the weaker CPU part of the APU than the other, causing broader performance issues unrelated to visual quality.
the "lag" mainly appears as screen freezing for about 2-5 seconds, often making the game feel choppy. also, when the GeForce restarts, it takes a while to redraw everything and load again, which can be noticeable. the Radeon handles that part quickly. his current APU is an A6 3650.
it's mostly occurs during Fortnite. he mostly plays random games on Roblox and has almost no problems there.
the main issue seems to be why this problem is happening rather than any other reason. I’m planning to upgrade tonight with a new system (except the GPU, which needs to wait until July).
I think getting a Radeon RX 580 with 8GB VRAM would help. Maybe a WD Blue SSD and a Samsung EVO drive could work if he’s really into it by his birthday. I’m not giving him more than $200 for a graphics card, and this should keep up until he probably becomes a teen.
Did you eliminate drivers that used DDU prior to exchanging GPUs?