Dear All,
I posted here a few days ago and got some helpful responses.
Dear everyone,
To study for the CompTIA A+ exam, I am using a book called “CompTIA A+ complete study guide, by Quentin Docter. Now, I am more than convinced he is probably a wizard with technical stuff, but it seems he shooto off a rapid speed when the basics are not explained very well.
He moves into bandwidth stuff with PCIe explanations very fast, and talk about bidirectional etc. I get bidirectional in theory - for example, “For the four versions a single lane, and therefore an x1 slot, operates in each direction (or transmits and receives from either communicating device’s perspective), at a data rate of 250MBps, 500MBps, approx 1gbps, and roughly 2gbps, retrospectivelY. An Associated bidirectional link has a nominal throughput of double these rates. Use the doubled rate when comparing PCIe to other expansion buses because those other rates are for bi-directional communication. This means that the 500MBps bi-directional link of an x1 slot in the first PCIe was comparable to the PCI’s best, a 64-bit slot running at 66MHz and producing a throughput of 533MBps.”
Considering about 2 pages (with pics) he was explaining what PCIe was (simple def), I am just really not sure what the fudge is going on! I get some of what he is saying - but a x1 lane if it was PCIe should be bi-directional to start with - no? So, why does a bi-directional suddenely have more than the line above’s figures (….at a data rate of 250MPBs, 500MBps…..)? I thought we were talking about bi-directional anyway?
It gets more complex on the next page when he starts talking about using identical graphic adapters and using a bridge!! I just can;t believe this is the really basic stuff - and if it is why it’s not brought in a little more gently than this. Basically, I don’t know what is actually going to be needed for this exam, and whats just then authoer going into more detail than strictly necessary?
Many thanks for reading - sorry if I am being a little more than “blonde”!
I posted here a few days ago and got some helpful responses.
Dear everyone,
To study for the CompTIA A+ exam, I am using a book called “CompTIA A+ complete study guide, by Quentin Docter. Now, I am more than convinced he is probably a wizard with technical stuff, but it seems he shooto off a rapid speed when the basics are not explained very well.
He moves into bandwidth stuff with PCIe explanations very fast, and talk about bidirectional etc. I get bidirectional in theory - for example, “For the four versions a single lane, and therefore an x1 slot, operates in each direction (or transmits and receives from either communicating device’s perspective), at a data rate of 250MBps, 500MBps, approx 1gbps, and roughly 2gbps, retrospectivelY. An Associated bidirectional link has a nominal throughput of double these rates. Use the doubled rate when comparing PCIe to other expansion buses because those other rates are for bi-directional communication. This means that the 500MBps bi-directional link of an x1 slot in the first PCIe was comparable to the PCI’s best, a 64-bit slot running at 66MHz and producing a throughput of 533MBps.”
Considering about 2 pages (with pics) he was explaining what PCIe was (simple def), I am just really not sure what the fudge is going on! I get some of what he is saying - but a x1 lane if it was PCIe should be bi-directional to start with - no? So, why does a bi-directional suddenely have more than the line above’s figures (….at a data rate of 250MPBs, 500MBps…..)? I thought we were talking about bi-directional anyway?
It gets more complex on the next page when he starts talking about using identical graphic adapters and using a bridge!! I just can;t believe this is the really basic stuff - and if it is why it’s not brought in a little more gently than this. Basically, I don’t know what is actually going to be needed for this exam, and whats just then authoer going into more detail than strictly necessary?
Many thanks for reading - sorry if I am being a little more than “blonde”!