Video card Upgrade options?

"A chain is a strong as its weakest link". We need to do a bottleneck analysis. The vast majority of the published maximum Bus speed for a single drive on a SATA Bus is simply not attainable.

Today's 7200 RPM drives source data off the platters at about 100 to 125 MBytes/sec. Be generous and say 128MBytes/sec*8bits/byte and you get 1024M bits/sec BEST CASE. That is a little faster than FireWire 800 speeds, and slower than 1.5 Mbits/sec eSATA.

Running the pipe at 6G bits a second does not speed anything up, unless we can somehow get more bits/sec off the drive.

With a free-standing RAID Array, you can eliminate some of the dead time while drives are seeking, but the transfer rate does not improve unless you can actually be transferring from multiple drives at once into a cache in the RAID card.

While your post is accurate with regard to real as opposed to theoretical transfer rates for sata, it chooses to ignore the fact that FW is likewise affected. I chose to compare published maxima for conformity, but actual speeds for FW vary from 90 to 65% of maxima, like sata this is dependent on several factors.

OK, I'm getting my bag of popcorn.

Nothing like a geek p.i.s.s.i.n.g match.....

YES, Firewire 800 is slower.

My basic assertion is that Firewire 800 produces "near Hard Drive" speeds.

6G SATA cannot improve on 1.5 eSATA unless you can actually transfer from multiple drives at once, not just overlap seeks.

Csound1 wrote:

Come on, it's not hard, in any chain the slowest link is the maximum speed available from the chain.

Your assumming the hard drive can maximize the bandwidth offered to it, it can't.

It's even more hobbled if it's doing extra duty like caching memory or VRAM like the (lower end MBP's tends to do) or if the drive is filling up and using the smaller sectors, it also has to complete one job before it can start another.

you have a hosepipe, it flows 1 gallon per minute, it matters not that the pump can supply 10 gallons per minute, only 1 gallon will emerge from the hose, per minute.

Using your pump and hose anology in the OP's case,

One pump is able to supply 2 gallons a minute over the SATA2 pipe being able to handle 20 gallons a minute = 2 gallons a minute.

Two pumps supplies 4 gallons a minute over a FW 800 pipe being able to handle 5 gallons a minute = 4 gallons a minute

Three pumps suppling 6 gallons a minute over a FW 800 pipe being able to handle only 5 gallons a minute = 5 gallons a minute.

Four pumps supplying 8 gallons a minute over the SATA2 pipe being able to handle 20 gallons a minute = 8 gallons a minute.

Interface speeds have improved tremendously, however hard drive speeds have not, especially for laptops.

Most all laptops still come with 5,400 RPM drives for the reason that higher speed drives (7,200-15,000 RPMs) are more suspectible to shock and can drain more power.

Using a RAID system that can split the data path (RAID 0, 5 etc) this allows more pumps to be used and can maximize the over all data transfer rate, free up the boot drive to be doing something else, like caching memory if they go over their RAM limit for instance.

Thanks for the laugh, it was dull until that.

Well if that's the best response you can do to support your argument, I guess this discussion is closed then. 🙂

Trying your suggestions out would be a good idea, for you.