Mac Pro 4.1 Ram of different capacities

[MacPaulli]

So i recently Got my 4.1 (flashed to 5.1), and trying to optimize the performance the Best i Can. I've been noticed long Black screen before boot chime, and it seems the Black screen is used to index the hardware afaik.
I have all eight ram slots filled out in my Dual socket tray, furthermore they consist of 1-2 GB blocks, giving a total of 17gb.
My question is this: Would you reckon I would see any performance/boot time gains from swapping the current ram setup with 4x4 blocks?

I've tried looking this up already, but i can't Seem to find a similar setup to mine.

Thanks

 

[reco2011]

Unfortunately I cannot directly answer your question. However it's my opinion it's foolish to spend money on a memory upgrade merely to decrease boot times.

 

[MacPaulli]

Well, it was not merely for boot times - but also overall performance. Faster boot times would be nice as well, but the reason i mentioned it was because the long black screen might indicate slow indexing of ram, which might also lead to slow performance when using heavy apps that take up lots of ram.
Seeing as I couldn't find much on the subject I thought someone here might have an answer .

 

[thefredelement]

I'd imagine it would do any type of EFI based probing pretty quickly.

Have you tried more classical things like resetting PRAM and/or the SMC, or the video card?

 

[MacPaulli]

I have tried both a SMC reset and PRAM reset, because that was my first thought as well. Thank you for the suggestion though . Over all i just think my Macs performance is a bit sluggish, all though it has an 8core 3.33 GHz, 17gb and a gtx 970. The sluggishness was also present before swapping the gnu though (had a 5870 mac edition).

 

[reco2011]

Well, it was not merely for boot times - but also overall performance. Faster boot times would be nice as well, but the reason i mentioned it was because the long black screen might indicate slow indexing of ram, which might also lead to slow performance when using heavy apps that take up lots of ram.
Seeing as I couldn't find much on the subject I thought someone here might have an answer .

More memory is helpful if you don't have enough of it. If your memory requirements are 8GB and you install 32GB the extra memory will not buy you much. In order to answer your question if more memory would be beneficial we'd need to know your memory requirements.

 

[RoastingPig]

Your 970 has no efi so it dosent have the boot screen

 

[MacPaulli]

I think the heaviest work i do is occasional photoshop. other than that its mostly gaming that would take up ram. My concern was more towards the low capacity on the ram blocks, and wondered if that would have anything to do with performance. Say if my mac was using 8gb of ram, would 2x4gb blocks be faster than the old stock ram of 2x2gb and 4x1gb blocks for instance? I should probably also mention that the current ram run at 1066 MHz where as I would be able to run new ones at 1333.

I know this is probably just a slight increase in performance overall. I was trying to locate the reason to the sluggishness on my mac as well as slow boot. I felt pretty convinced that the it was due to the ram blocks, but the reason might be elsewhere then, i guess .

Your 970 has no efi so it dosent have the boot screen

I know it doesn't, but as I mentioned the long black screen before the chime was also present before changing the gpu.

 

[reco2011]

I think the heaviest work i do is occasional photoshop. other than that its mostly gaming that would take up ram. My concern was more towards the low capacity on the ram blocks, and wondered if that would have anything to do with performance. Say if my mac was using 8gb of ram, would 2x4gb blocks be faster than the old stock ram of 2x2gb and 4x1gb blocks for instance? I should probably also mention that the current ram run at 1066 MHz where as I would be able to run new ones at 1333.

I know this is probably just a slight increase in performance overall. I was trying to locate the reason to the sluggishness on my mac as well as slow boot. I felt pretty convinced that the it was due to the ram blocks, but the reason might be elsewhere then, i guess .

You mention the system has 17GB of memory already. Do you regularly work with images which push that limit? If not then it's unlikely more memory is going to benefit you. The same with games...they're not know to push 17GB memory limits.

Regarding the matching of modules I see where you're coming from. Depending on the number of memory channels larger quantities of smaller capacity modules provide more bandwidth. For example 4 x 1GB modules can provide more memory bandwidth than 2 x 2GB modules. This is a gross simplification but, for any given capacity, Sun systems recommended buying more, smaller capacity modules in order to increase bandwidth.

In real world cases for end users you're unlikely to see such benefit. IMO using larger capacity modules provides headroom to grow (IMO having more memory is better than having less memory but slightly more bandwidth).

An easy way to test if the different modules are causing the system to take longer to POST is to remove the different modules. To the extent possible leave matching capacity DIMMs in place and remove everything else.

 

[h9826790]

You should not able to notice any real world difference for different RAM configuration (as long as you have enough RAM).

For benchmarking software, yes, your RAM can score 50% more by optimising the triple channel architecture and run the RAM in 1333MHz. However, even though benchmarking software, you may only see about 5% difference in overall performance. In real life, may be 2% or less for most of the time.

Apart from the graphic card, is there anything else in the PCIe slot? Do you have any external HDD? A long black screen before the chime may be an indication of slow hardware initialisation. Any non-native hardware may contribute to this issue.

 

[MacPaulli]

You should not able to notice any real world difference for different RAM configuration (as long as you have enough RAM).

For benchmarking software, yes, your RAM can score 50% more by optimising the triple channel architecture and run the RAM in 1333MHz. However, even though benchmarking software, you may only see about 5% difference in overall performance. In real life, may be 2% or less for most of the time.

Apart from the graphic card, is there anything else in the PCIe slot? Do you have any external HDD? A long black screen before the chime may be an indication of slow hardware initialisation. Any non-native hardware may contribute to this issue.

Well, im booting from a XP941 256GB drive in a Lycom DT120 adapter. I know that drive is recognized as a external drive, but could that really be whats holding up the mac for so long?

You mention the system has 17GB of memory already. Do you regularly work with images which push that limit? If not then it's unlikely more memory is going to benefit you. The same with games...they're not know to push 17GB memory limits.

Regarding the matching of modules I see where you're coming from. Depending on the number of memory channels larger quantities of smaller capacity modules provide more bandwidth. For example 4 x 1GB modules can provide more memory bandwidth than 2 x 2GB modules. This is a gross simplification but, for any given capacity, Sun systems recommended buying more, smaller capacity modules in order to increase bandwidth.

In real world cases for end users you're unlikely to see such benefit. IMO using larger capacity modules provides headroom to grow (IMO having more memory is better than having less memory but slightly more bandwidth).

An easy way to test if the different modules are causing the system to take longer to POST is to remove the different modules. To the extent possible leave matching capacity DIMMs in place and remove everything else.

I dont think i have ever used image files that big tbh. I might, on the other hand, have been running too many apps at the same time causing all the ram to be used up - but thats a rare scenario. Considering the mac is sluggish without anything else open but safari, i'm guessing RAM is not the issue then. Thanks for clearing up.
I wonder what might be the problem then.

 

[xcodeSyn]

Well, im booting from a XP941 256GB drive in a Lycom DT120 adapter. I know that drive is recognized as a external drive, but could that really be whats holding up the mac for so long?

There is the reason for longer pause before the chime as h9826790 suggested before. Anyone who has installed extra PCIe cards would notice a longer pause because it takes extra time to initialize the extra hardware. If you don't like the wait, just put your machine to sleep instead of shutting it down. If you want to confirm it, remove the Lycom adapter and use an internal boot drive to observe the difference. BTW, how is it possible to have 17GB RAM when using only 1 and 2GB memory modules for 8 slots unless I misunderstood?