Sorry I'm not giving clear questions. I did the firmware conversion and got High Sierra to install on another internal HD. Now I have to see what app's will install. Hard to find DMG's of stuff I downloaded a few years back. My real issue was waiting till next year for the new Mac Pro's and then spending maybe 3k. My pockets aren't that deep. So I set a budget for this machine of around 1k in up grades. I won't do myself installing a new cpu, I guess I would send it to OWC but then I would be shut dow for who knows how long and I forgot what they would charge for that? I don't know if any of you are graphic designers, if not the old problem of photoshop while saving and other things with a file, PS makes it 4 times larger then after saving is finished it it's normal size. With some poster I do I may have many layers in the file that makes it larger and it's not uncommon to be working on a 100MB file. I agree on the internal SSD. I talked with Samsung yesterday and they told me with my Mac the way it is right now I would loose 30% of the SSD's speed. But you see I've been on this Mac for so long any change toward speed is going to feel great. Thanks all for hanging with a geezer of 70.
Don't worry about the speed, what you focus on is the high IOPS, almost none of the SSD I know has 250MB/s on the 4k random read speed (most of them are just 30MB/s even the PCIe SSD), your Mac won't pull you down too much on real world usage.
Think in this way. e.g. your "large" 100MB file.
For a HDD, it can easily go >100MB/s on the sequential read speed. Even my so call "slow" WD Red HDD can achieve 160MB/s. That means, if the HDD can deliver that on your 100MB file. The loading will be finish just within 1 second.
For a SSD, let's say 500MB/s for a typical SATA SSD, in can finish the loading in 0.2s.
For human being, no big difference, still finish the loading within 1 second.
However, why SSD is so much faster? Because that 100MB file consist of many different layer, the data may actually spread all over the place. The HDD may need to search >1000 different location to pull all the required data.
Now the game changed. It's not depends on the sequential read anymore, but random read speed. It's all about how fast the hard drive can locate the data. This is why SSD is so "fast".
For that same 100MB data. On a HDD, the usually 4k random read speed is just ~1MB/s. Therefore, in worst case (all data really split into multiple 4k random blocks). It will require 100s to finish the loading.
But on a SSD, it's about 30MB/s. Therefore, the loading will be finished within 4 seconds.
Now, on human being feeling. The SSD is much faster.
Will the SATA II connection limit anything? NO in this case.
I bought the same 09 Mac Pro with W3520 back in 2009 directly from Apple. I went through the upgrade route. I know what's the really useful stuff.
A SSD on a SATA II or SATA III port, doesn't really matter on most operation (apart from copying very large files, including (un)zipping, which is also a kind of copying). And you don't need any super fast SSD.
To play safe, I will recommend a Samsung 850 Evo to you. However, really, any SATA SSD can do the job (except the OWC SSD), the cheaper the better. No point to spend too much on this item. My "$500 1TB Samsung 840 Evo installed on a Tempo SSD SATA III card" work more or less the same as my "$30 120GB DGM SSD just plug into one of the native SATA II port). (Anyway, you can click the items in my signature to jump to the corresponding link).
However, if your issue is something like "photoshop slow respond when using large brush", then both SSD and memory won't help. You may really need a better CPU or GPU depends on what you were doing.
I also suggest that don't worry about the CPU upgrade at this moment, get the SSD, and may be more RAM first (recommend start with 3x8GB, only go higher if you clearly know that you are bottleneck by memory size). Try it, and if you still feeling "too slow", then consider the CPU upgrade.
