[SOLVED] Is PCIe 4 worth the upgrade?

[fureniku]

Hey all,

So, straight to it. I've been building a new PC, everything is ready to go except the GPU, which I was waiting on the nVidia announcement for. During the announcement, they mentioned the new cards are PCI 4.

This hadn't even crossed my mind when I was researching motherboards (and wasn't really mentioned in any threads detailing why motherboards may be more or less expensive), and my MSI Tomahawk is only PCI 3.

Now, I know the card will still work fine so this isn't the end of the world. My question though, is if it would be worth it for me to upgrade to a MoBo with PCI 4 while this one is still as new/unused (bar a brief system test). I wouldn't be able to return it but I could probably get a decent price on eBay.

I had a look around the web and only really found two things about the difference. One said PCI 4 is twice as fast on paper, and the other was comparing FPS benchmarks by switching between 3 and 4 in the bios with very little difference. What's the likely real-world situation, would I see a big enough performance difference to warrant the upgrade?

If it matters, I'll be going for the RTX 3080.

Thanks!

 

[sizzling]

Hotly debated topic that won’t get answered until benchmarks are available.

 

[drea.drechsler]

... What's the likely real-world situation, would I see a big enough performance difference to warrant the upgrade?
...

Steve gives you the best analysis. He's illustrates bandwidth improvement using gen 2 to gen 3 with both Nvidia and AMD GPU's but only has RX5700/XT's to demonstrate scaling with gen 4 so how it scales with the 3000 series from nvidia remains to be seen.

Personally, I think it will matter some but not enough to make you toss a perfectly good motherboard that only supports gen 3. But if a motherboard upgrade is required for other reasons I'd certainly put it in the budget.

View: https://www.youtube.com/watch?v=PAwIh1nSOQ8

 

[Zerk2012]

It's not going to be close to filling the bandwidth of 3.0 so any difference will be very little if any of course under certain conditions their will be a few exceptions.


From just the bandwidth prospective PCI-E 2.0 X16 was just saturated with a 2080ti
Note that 3.0 X8 is a bit less than 2.0 X16.

https://tpucdn.com/review/nvidia-ge...ress-scaling/images/pci-express-bandwidth.png

https://tpucdn.com/review/nvidia-ge...ing/images/relative-performance_1920-1080.png

If you look at it in FPS if it did give a 5% performance increase and you were getting 100 FPS in a game then it bumped you up to 105 FPS if your CPU can process that many then it's not really enough to even matter.

EDIT I have a 1440p Ultrawide 144hz monitor ordered 21:9, have a 3.0 slot and when the MSI RTX 3080's are released I'm buying one. I'm in no way stressed over loosing performance.

 

[bniknafs9]

yes , it will give you super fast speeds on your M.2 drive

 

[glennhl]

My 500 gb NVMe on PCIe 4.0 (X570 MB) Read: 5000 mb/s, Write: 2500 mb/s
My 500 gb NVMe on PCIe 3.0 (B450 MB) Read: 2500 mb/s, Write: 1800 mb/s

 

[sizzling]

My 500 gb NVMe on PCIe 4.0 (X570 MB) Read: 5000 mb/s, Write: 2500 mb/s
My 500 gb NVMe on PCIe 3.0 (B450 MB) Read: 2500 mb/s, Write: 1800 mb/s

Unless running a benchmark could you actually tell the difference? I can’t feel any difference between SATA and NVMe which is a much bigger gap on paper.

 

[glennhl]

Unless running a benchmark could you actually tell the difference? I can’t feel any difference between SATA and NVMe which is a much bigger gap on paper.

No, it's not worth it! My wife's computer (B450) starts up quicker than mine (X570). However, I can tell the difference from SATA when I go to load on a track on iRacing. Used to take over 2 minutes and now it's close to 30 seconds. I haven't compared the track loading on my wife's computer, but it's probably only a few seconds difference.

 

[USAFRet]

Unless running a benchmark could you actually tell the difference? I can’t feel any difference between SATA and NVMe which is a much bigger gap on paper.

^^^ Exactly that.

In my system, actual testing and actual use case...I cannot tell the diff between a 1TB Samsung 860 EVO (SATA III) and a 1TB Intel 660p (NVMe).

 

[drea.drechsler]

No, it's not worth it! My wife's computer (B450) starts up quicker than mine (X570). However, I can tell the difference from SATA when I go to load on a track on iRacing. Used to take over 2 minutes and now it's close to 30 seconds. I haven't compared the track loading on my wife's computer, but it's probably only a few seconds difference.

A more relevant comparison would be to lock your PCIe at gen 3 on the X570 (should be able to do that with a BIOS setting). Then re-create the exact same track load and what do you get then.

Comparing start-up to Windows on two completely different systeems is not as straight forward as it may seem. Way too many variables are in play.

 

[DeauteratedDog]

Unless running a benchmark could you actually tell the difference? I can’t feel any difference between SATA and NVMe which is a much bigger gap on paper.

While it might not make much difference on a gaming or general use PC, it will make a huge difference for PCs running disk-io bound applications - like database servers.

 

[USAFRet]

While it might not make much difference on a gaming or general use PC, it will make a huge difference for PCs running disk-io bound applications - like database servers.

There are absolutely use cases where it makes a difference.

Minecraft at 720p is not that.
Booting up 0.3 sec faster is not that.
Copying to and from a USB 2.0 flash drive is not that.