Question RX 6600 Shader units half of what they are ment to be

Jun 15, 2022
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I recently checked on GPUZ what my specs are compaired to what they are supposed to be and noticed my shader units are 896 instead of 1792, the TMUs are half as well and the bus interface is PCIe x8 4.0 @ x8 1.1 and saw a video where their one was PCIe x8 4.0 @ x8 4.0, im not sure if this is a problem that i should be worried about.

I have a AORUS B450 M motherboard and an ASUS Dual RX 6600
 
I recently checked on GPUZ what my specs are compaired to what they are supposed to be and noticed my shader units are 896 instead of 1792, the TMUs are half as well and the bus interface is PCIe x8 4.0 @ x8 1.1 and saw a video where their one was PCIe x8 4.0 @ x8 4.0, im not sure if this is a problem that i should be worried about.

I have a AORUS B450 M motherboard and an ASUS Dual RX 6600

First question, are you using the latest version of GPU Z? It might be that it is incorrectly identifying the card - there have been cases with scammers have rebadged older or lower tier cards as higher models however looking at the specs you list I don't know of any cards that have 896 stream processors and also support PCIe 4.0. Looking at the official specs for the RX 6600 that is a PCIe 4.0 x 8 card so that is at least correct.

The best way to check if the card is ok or not is to run a performance benchmark - I suggest using the free 3D Mark Timespy demo on steam. That will give you a score and compare against similar cards, 3D Mark also lists the specs in the results page and should be up to date.
 

Eximo

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Without a load the GPU will drop down the PCIe speed to save power, that is normal.

3D Mark has the RX6600 listed as doing 8131, yours is only a little behind that. And your test reported some settings that need to be modified for a valid score so I wouldn't use that as a definitive result. Not to mention that there will be a lot of overclocked scores in there that you are up against.
 
Jun 15, 2022
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i have oc my gpu a small bit to 2530 and memory to 1810 if that matters, im game like forza horizon 5 using the same preset and compairing to youtube vids with the same specs they get alot more fps than me aswel, its confusing
 

Eximo

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When troubleshooting performance you should not have an overclock enabled.

Double check your overclock is actually successful. Recoverable errors in the memory, for example, can be the cause for slowdowns as more clock cycles are needed to re-do the work.

Clock frequency is nice to have, but consistency can be better overall. If you overclock, that means the temperatures will be increased, with increased temperature the GPU may throttle more than it would have stock. While it might not be crashing, that doesn't mean it is performing consistently. As another example; On a lot of cards, an undervolt can actually increase performance since the GPU will stay boosted a little longer.
 
Jun 15, 2022
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even when my gpu is under load it still saying its in PCIe x8 4.0 @ x8 1.1 is that fine? and no global settings are on other than sharpening and surface format optimization
 

Eximo

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Well, the CPU supports 4.0, but the motherboard never really did. Maybe try updating the motherboard BIOS to the latest?

Or forcing PCIe 3.0 mode in the BIOS.

It could be that it is struggling to get 4.0 working on the slot and is defaulting to the lowest speed? Just a guess though.
 
So i have updated to the latest bios update but didnt do anything for me, i then forced the PCIe to 3.0 in the bios but that did nothing it didnt change at all but forcing it to 2.0 worked and gave me an extra 10 - 13 fp, but im just so confused to why it wont go to 3.0. the shader units are still the same 896, this is what GPU Z is showing now View: https://imgur.com/a/7Ft4yB4

The performance numbers you are getting in TimeSpy suggest that your card is OK - the issue must be elsewhere. I notice GPUZ isn't listing clock speeds so it's not identifying the card correctly. It's also strange that it won't work with PCIe. 3.0 on that motherboard?

Did you upgrade to the RX 6600 from an older card recently? If so it could be a drivers issue - you could try doing a full clean install of the graphics drivers and see if that resolves some of the issues... To do this use the free 'DDU' (display driver uninstaller) tool to fully remove the current drivers from your machine, then download and install the latest drivers directly from the AMD website.

I would also recommend installing the latest AMD chipset drivers from the AMD website as these can sometimes resolve strange issues.
 
@EV0X
Resizable BAR is not enabled in bios according to GPU-Z and your system ram speed is 2800MT/s. Those 2 things could be holding back performance in games and especially Forza Horizon 5.

Did you buy a 2800MT/s ram kit or are you just running it at that speed for some technical reason? Also, you should leave PCIe on Gen 3.0 or Auto, so you don't potentially lose performance and I'm also not sure if Resizable BAR gets disabled when switching PCIe below gen 3.

View: https://www.youtube.com/watch?v=FM-mDf0U38k&t=442s
 
Jun 15, 2022
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So i used DDU and reinstalled the latest drivers and also got the new amd chipset drivers, i enabled resizeable BAR , i bought my ram at 2400 idk why it was showing as 2800 before but is not any more, the only problem i can see is the bus interface when its set to auto and under load it stays at PCIe x8 4.0 @ x8 1.1 and it stays at that when forced to 3.0, but forced to 2.0 putting it to PCIe x8 4.0 @ x8 2.0 works giving the same performance boost.
what GPU Z is showing now View: https://imgur.com/a/JE73C71


TimeSpy (bus interface set to auto/3.0, they had the same results) https://www.3dmark.com/3dm/76376970
TimeSpy (bus interface set to 2.0) https://www.3dmark.com/3dm/76377303

i am getting more fps in forza now i was getting 47 and now 72 but its saying i stuttered 200 times compaired to 2 View: https://imgur.com/a/6zohWCT
View: https://imgur.com/a/xELx4eV

Forza benchmark with resize bar off (no stuttering but less fps) View: https://imgur.com/a/ynOGrzl
 
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the only problem i can see is the bus interface when its set to auto and under load it stays at PCIe x8 4.0 @ x8 1.1 and it stays at that when forced to 3.0, but forced to 2.0 putting it to PCIe x8 4.0 @ x8 2.0 works giving the same performance boost.
This is how it's suppose to function because it's a power saving feature for when the GPU has no graphics load. You don't need to mess with with the PCIe gen settings in the bios in your current situation as it won't actually help you. You will lose performance running forced PCIe 2.0 from the bios settings.

Your RX 6600 is a PCIe 4.0 card, but your motherboard only supports PCIe 3.0. AMD removed PCIe 4.0 support from the 400 series bios updates so that people don't complain about having issues with PCIe 4.0 not functioning properly on their board, which was never designed to use PCIe 4.0 in the first place. They initially added PCIe 4.0, because of the newly released PCIe gen 4 NVMe SSDs and the upcoming x570 chipset motherboards, but is now only usable on 500 series motherboards with current bios release.
 
Even under load it doesn't change it stays at 1.1 and won't force to 3.0, only to 2.0 which I get better performance on compared to 1.1
It's very likely happening because you are moving focus away from the game or program and giving it to GPU-Z when checking it. Run a game in windowed mode and then check it with both on screen at the same time and it should show PCIe 3.0 x8.