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really disappointed in zen4 APU performance

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Space Lynx

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Got a 7640u laptop for work recently, was hoping to be able to utilize the APU to save battery when traveling, etc. screen is 1200p, but even an ancient game like company of heroes can't get a full stable 60 fps at high settings. man why is it so hard to find a basic portable no giant power brick work laptop that can do some light gaming?

zen4 APU just isn't good enough unless its the 7840hs or 7840u, that's where it shines. I regret my purchase. oh well. I tried a demo display of a Intel raptor lake integrated graphics laptop at Microcenter and it was playing more demanding games than company of heroes at 60 fps... this is just sad how bad AMD cut it down just to please their stack. its pathetic you can't buy a 7840u by itself for 500 bucks in laptop form. every single manufacturer forces you to pair it with dedicated GPU or an OLED screen dramatically rising the cost and portability factor cause of the power brick that gets introduced too. free markets my ass. huge missed opportunity AMD.
 
Seems like it has 760M, should still be somewhat capable for an IGP. Could it be power throttling?
 
it's the 7540u not the 7640u I had it wrong.

no its not power throttling, its just a cut down version of an already cut down version... couldn't find any reviews of it when I got it. but I was like well its zen4 4nm node, it will be fine. and yeah its not fine. its a scam. absolute joke it cant even run company of heroes properly. that game is ancient.
 
Hello, I recommend to go and install the latest version of AMD drivers. Then use their latest technology RSR+AFMF+RAL how to open the software is introduced on AMD's official website.
Personally, I use AM5 7600x internal display with only 2PCS GPU to play CS2 with 50-70FPS. Hope it helps:) you
PS. I don't understand English. It's all Google Translate
 
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Maybe try another game ?
COH could be old but demanding too ...
 
you can't buy a 7840u by itself for 500 bucks in laptop form. every single manufacturer forces you to pair it with dedicated GPU or an OLED screen dramatically rising the cost and portability factor cause of the power brick that gets introduced too. free markets my ass. huge missed opportunity AMD.

That is literally not AMD's decision. They sell chips. They don't dictate to ODMs how those chips are used. See: the entire history of Bulldozer based APUs being hamstrung by single-channel bargain barrel DDR3 for 5 years straight. ODMs build what they think will sell, and they don't think a top-spec APU without an accompanying dGPU will sell.
 
Yeah with only 256 cores, the 7540u isn't going to be playing many games at particularly high framerates. One thing to check is if you have dual channel ram installed because single channel will hamper performance even more.

One possible issue with COH is that it's a DX9 game and I have no idea if RDNA3 APUs have any trouble with old DX9 titles.
 
it's the 7540u not the 7640u I had it wrong.

no its not power throttling, its just a cut down version of an already cut down version... couldn't find any reviews of it when I got it. but I was like well its zen4 4nm node, it will be fine. and yeah its not fine. its a scam. absolute joke it cant even run company of heroes properly. that game is ancient.

Phoenix-2 iGPU is pretty bad, unfortunately. I don't think anyone was under any illusion otherwise, and I really don't think even LPDDR5x would solve that problem. Last gen needed 6CUs to match even Vega iGPU performance. You'll need either the full Phoenix or Hawk Point die without any E-cores, for the iGPUs that actually matter (8CU and 12CU).

I said this back then that it's incredibly scummy for AMD and OEMs to be slipping 7540U into notebooks as the entry level Phoenix choice, even before PHX-2 was properly understood. Since there's a huge difference between the two 6 cores, 7540U and 7640U. Looks like things haven't changed as Hawk Point has the same SKU lineup.
 
Phoenix-2 iGPU is pretty bad, unfortunately. I don't think anyone was under any illusion otherwise. You'll need either the full Phoenix or Hawk Point die without any E-cores, for the iGPUs that actually matter (8CU and 12CU).

7540U is not Phoenix2. That'd be the 7545U. 7540U is the bog-standard 6-core with Radeon 740M, the lowest possible cut of RDNA3.

7545U announcement and product page arrived months later, 7540U was understood from its first appearance in ThinkPad T14/P14 Gen4 to be debuting the PHX-2 die. I know AMD website has been changed to show 7540U as 178mm^2, but all the other info I've seen up to this point backs PHX-2. Unless you have any additional links you can post.

How about AMD's official slide deck for the announcement of Zen4c in laptops which specifies the difference between the 7540U as 6 Zen4 cores and the 7545U as 2+4 Zen4+Zen4c. Phoenix2 is specifically and only inclusive of hybrid architecture SKUs.

1711435243120.png
 
7540U is not Phoenix2. That'd be the 7545U. 7540U is the bog-standard 6-core with Radeon 740M, the lowest possible cut of RDNA3.



How about AMD's official slide deck for the announcement of Zen4c in laptops which specifies the difference between the 7540U as 6 Zen4 cores and the 7545U as 2+4 Zen4+Zen4c. Phoenix2 is specifically and only inclusive of hybrid architecture SKUs.

View attachment 340664

Yes, that's why the post was deleted
 
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You were too fast on that while I was digging up the press deck from my database folder.

I was just going off unofficial reports from last year, before the 7545U announcement. People were saying there isn't really much to prevent AMD from theoretically dual sourcing 7540U. But it seems like that was a rumor after all, after the 7545U release slides.

its pathetic you can't buy a 7840u by itself for 500 bucks in laptop form. every single manufacturer forces you to pair it with dedicated GPU or an OLED screen dramatically rising the cost and portability factor cause of the power brick that gets introduced too. free markets my ass. huge missed opportunity AMD.

Even if 7640U was borderline vaporware, this seems like misplaced expectations, though. It's not like you can get 128EU Meteor Lake in anything below -H TDP either, and most of the mobile Raptor Lake is full 80/96EU. I've seen either iGPU-less 7840U or 7840HS around if not a bit below the 1000usd mark which seems about right. It just doesn't make sense for AMD to adopt their 7000/8000 stack strategy and then put 7840U/8840U in a low-end product.
 
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yeah I was an idiot and not paying attention to the graphics core count.

its not the end of the world, but for 500 bucks I was expecting more performance for the price I paid. /shrug

Finally not bad, my 5700G has 8.
 
yeah I was an idiot and not paying attention to the graphics core count.

its not the end of the world, but for 500 bucks I was expecting more performance for the price I paid. /shrug

What's the model of laptop?

If you can stomach a little more price tag, I've seen the Flow X13 (iGPU version) and Zephyrus G14 (16GB, 4060) both come down to the 899 mark in recent months. If I lived in US I would have sold my G14 2022 in a heartbeat for that Flow. But I'm afraid 500 is a little too low, not only for 7840/8840 but even 7735/6800/6900HS. I don't expect to see 7840/7940 -U or HS below 800usd, ever.
 
i have a 610m (which is basically the iGPU of the desktop non G Zen 4 Chips and half of yours (128 Core)
even on a zen 2 Chip it runs WoW and even R6 Siege at 720p with 70-80 FPS.

do you have the latest chipset and GPU drivers installed?
 
I don't understand. You bought a laptop with a weak iGPU, and now you're complaining that the iGPU is weak?
 
It has 8 CUs, what did you expect, it's going to be in same range of performance as a 5700G.
 
i have a 610m (which is basically the iGPU of the desktop non G Zen 4 Chips and half of yours (128 Core)
even on a zen 2 Chip it runs WoW and even R6 Siege at 720p with 70-80 FPS.

do you have the latest chipset and GPU drivers installed?

What's the memory subsystem on the Mendocino look like though? Wouldn't be surprised if the cheap $500 laptop is using either a single SO-DIMM or has an unpopulated SO-DIMM slot.

It has 8 CUs, what did you expect, it's going to be in same range of performance as a 5700G.

8CUs would be near 12CU performance as already tested many times in 8600G and 7640U. This one is 4CUs.
 
It has 8 CUs, what did you expect, it's going to be in same range of performance as a 5700G.
Nah, the 7540U has only 4 CUs. It's only slightly better than a Zen 4 desktop iGPU which is a glorified display adaptor, nothing else.
 
What's the memory subsystem on the Mendocino look like though? Wouldn't be surprised if the cheap $500 laptop is using either a single SO-DIMM or has an unpopulated SO-DIMM slot.
my laptop was 299€ (literally the cheapest crap that has an IPS Panel)
It's a 7520U with two 4GB 5500 LPDDR5 Modules soldered in one channel.
 
The initial criticism is 100% relevant though. I often complained about Intel gatekeeping their best iGPUs to pricier SKUs that nobody but Apple and Intel's own NUC carried, which made them useless for a cheaper laptop. Now Intel at least allows (best case):

i7: 96CU Xe, 768 shader
i5: 80CU Xe, 640 shader
i3: 64CU, 512 shader

But with AMD and their even better iGPU:

R7&9: 12CU, 768 shader (Radeon 780)
hi R5: 8CU, 512 shader (Radeon 760)
R3+5: 4CU, 256 shader (babyeon 740)

So the best R5 gets an iGPU that's already cut to the level of something you can get in an i3 Intel CPU and some further cut to half that amount. And that full Radeon 780 iGPU is gatekept behind far better dGPUs as that CPU is only used in dGPU gaming systems. That's a kick in the nuts and I hate it. I started PC gaming on an Intel Iris iGPU NUC and still do some iGPU gaming on occasion so I'm interested in this but more weirdly:

The R7 and 9 iGPU gaming tail that's wagging the dog is Mini PC gaming. There are lots of R7 and R9 Mini PCs with that tasty full Radeon 780 12CU iGPU, while there are like 3 total Mini PCs with mobile dGPUs in them. Totally the reverse of the gaming laptop market. It's strange, man.
 
The initial criticism is 100% relevant though. I often complained about Intel gatekeeping their best iGPUs to pricier SKUs that nobody but Apple and Intel's own NUC carried, which made them useless for a cheaper laptop. Now Intel at least allows (best case):

i7: 96CU Xe, 768 shader
i5: 80CU Xe, 640 shader
i3: 64CU, 512 shader

But with AMD and their even better iGPU:

R7&9: 12CU, 768 shader (Radeon 780)
hi R5: 8CU, 512 shader (Radeon 760)
R3+5: 4CU, 256 shader (babyeon 740)

So the best R5 gets an iGPU that's already cut to the level of something you can get in an i3 Intel CPU and some further cut to half that amount. And that full Radeon 780 iGPU is gatekept behind far better dGPUs as that CPU is only used in dGPU gaming systems. That's a kick in the nuts and I hate it. I started PC gaming on an Intel Iris iGPU NUC and still do some iGPU gaming on occasion so I'm interested in this but more weirdly:

The R7 and 9 iGPU gaming tail that's wagging the dog is Mini PC gaming. There are lots of R7 and R9 Mini PCs with that tasty full Radeon 780 12CU iGPU, while there are like 3 total Mini PCs with mobile dGPUs in them. Totally the reverse of the gaming laptop market. It's strange, man.
That's because that R7 is Phoenix 1 based which has physically 12 CUs on it, while lower R5s and R3s are Phoenix 2 based with only 4 CUs. They're cheap parts for people with low expectations.

One must do the research before buying anything.

Edit: I'm not saying this practice is right, though. Laptops should come with beefier iGPUs. But still...
 
That's because that R7 is Phoenix 1 based which has physically 12 CUs on it, while lower R5s and R3s are Phoenix 2 based with only 4 CUs. They're cheap parts for people with low expectations.

One must do the research before buying anything.

Edit: I'm not saying this practice is right, though. Laptops should come with beefier iGPUs. But still...

The R5s have both Phoenix and Phoenix 2 SKUs and the regular Phoenix SKUs have options for both the 8CU (R5 7640) and 4CU (R5 7540) option. Yeah that lonely R3 is a Phoenix 2, though.
 
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